"Bad books on writing and thoughtless English professors solemnly tell beginners to Write What You Know, which explains why so many mediocre novels are about English professors contemplating adultery."
You don't say?
Seriously, though. In fiction, it is relatively common for the main character to be a writer or a reporter. This is in large part because many narrative works of art are initially driven by writers themselves (novelists, playwright, screenwriters, etc.)
Interestingly, such characters are only occasionally Author Avatars. As the page quote indicates, one of the main pieces of advice writers hear is "Write What You Know", and since, as writers, they know writing, they have some idea how a writer would react in a given situation. This trope is almost unavoidable when the setting revolves around a Show Within a Show, and may lead to a Writer's Block Montage. Making characters who are writers by trade has a number of advantages for a narrative.
Even if they don't use those skills in the plot, journalists are generally close to a wide variety of local important people like politicians and big events like disasters, but not actually one of those people or part of those events. This is the in-universe reason why Superman and Spider-Man went into journalism in the first place, so they could keep their ears to the ground and find out when and where superheroes are needed.
Freelance writers and journalists have a semi-plausible excuse for their One-Hour Work Week.
Fiction writers in-universe, because of that same "write what you know" principle, can theoretically have every Chekhov's Skill an amateur could plausibly have if they had researched it for a book.
In Ichigo Mashimaro, Miu tries her hand at being a writer of manga, but her works are a bit surreal for Chika.
Bakuman。 is a manga about manga, with the main characters being a manga artist and author, and is coincidentally produced by a writer and an author as separate people.
Himeko's mother from Himechan No Ribon is a writer of young women's romance novels who often takes ideas from the real world into her stories, with little changes.
Galaxy Express 999 does this several times. At one point, a poor person Tetsuro meets is a would be anime creator (who we are told, did manage to get her anime created), and episode 58 features a ghost who was a would-be manga writer in life. Episodes 60-61 have another would be manga artist, and another one shows up in episode 101. And 111 too.
Fairy Tail has Supporting Protagonist Lucy who has spent much of the series on writing a book. The trope is even played with when she tries to trick a villain by saying she needs to go the bathroom. The villain has prepared for such a cheap trick and shows Lucy a bucket that she may use instead of a toilet. Lucy pretends that she is actually going to use the bucket. The villain is embarrassed and looks the other way, and Lucy uses the opportunity to kick him in the crotch. She then notes that despite the bathroom trick being one of the oldest ones in the book, it actually worked, and that she might use it in her own novel.
Wakanae Sora of Family Compo is a manga artist, who seems to specialize in manly action stories if the covers of Our Emblem are anything to go by.
Yuuki Rito's father in To Love-Ru is a manga artist who rarely sees his children because he's constantly on deadline.
The bodyguard/chief enforcer of an intergalatic warlord becomes Mr Yuuki's assistant. Somehow.
Nitori from Wandering Son shows a knack for writing throughout the series, typically being the one to write scripts for the school plays and often shown writing. In high school she even begins writing a book that can best be described as an in-universe version of the manga. When she goes to college at the end of the manga she says she wants to get into a writing-related career.
Daniel Clowes (Eightball) frequently writes about artists and writers. Enid Coleslaw of Ghost World was an artist, as is Dan Pussey of Pussey! It's alluded to in David Boring that the title character is a multimedia artist. At least two of the main characters (including the main character) of Ice Haven are writers. Twentieth Century Eightball is a collection of short-stories from Clowes, many of which are about artists (Art School Confidential, Ink Studs, etc.).
Naruto in A Growing Affection ghost wrote for Jiraiya during the time skip, and helped with the outline for the next few books as well.
Vale, the protagonist of the Hunger Games fanfic Some Semblance of Meaning, wants to be a writer, even if she simultaneously acknowledges this aspiration as "unrealistic." Her writer's mind affects her perception of events at times, and her storytelling actually comes into play when Kit asks her on his deathbed to tuck him in, and she tells him about a "land without districts" where good people go when they die, and later, when she echoes that story during the final confrontation.
Barton Fink is about a writer suffering from writer's block, written while the Coens themselves were having difficulty with Millers Crossing. This writer really wants to make arty, weighty, important movies about the plight of the common man, similar to his successful play, but gets assigned a wrestling picture instead.
In the film Croupier the protagonist (played by Clive Owen, no less) is a novelist working as a croupier for a day job. The film really starts to get interesting when he commences writing a thinly disguised roman á clef entitled "I, Croupier", the plot of which resembles his own life.
Charlie Kaufman's Adaptation is a particularly surreal take on this trope. Kaufman himself (as played by Nic Cage) is the protagonist, and the movie is at least in part about the writing of itself. Then it gets even more surreal. The writer credits for the movie include Donald Kaufman, Charlie Kaufman's fictional twin brother, who's also a character in the movie, and also a writer (and also played by Nic Cage).
Sunset Boulevard: Protagonist and narrator Joe Gillis is a screenwriter, and this proves important — he catches Norma Desmond's interest as she believes he can help her complete the script of her great comeback film. To complete the triangle, Joe's girlfriend Betty is another aspiring screenwriter.
Gordie, the protagonist of Stand by Me, writes and tells stories as a teenager; the movie ends by showing us the now-adult Gordie writing the events of the film on his computer, while his son irritably waits to be taken to the pool.
Brother Gilbert in Dragonheart wants to compose epic ballads, and spends part of the film trying to write one about protagonist Bowen.
It would be shorter to list the Woody Allen movies where one of the main characters isn't a writer.
Romancing the Stone is about a female author who gets pulled into a treasure hunt alongside a rugged male adventurer played by Michael Douglas. It was written by a female writer who got pulled into the world of Hollywood by Michael Douglas.
In Withnail and I, the character only officially known as "I" is a writer, but all he writes is "just thoughts, really." His writing serves as the movie's occasionally Fauxlosophic Narration.
In How To Lose Friends And Alienate People, which based on a memoir by a British journalist, most of the characters are journalists (and a lot of them have hobbies such as writing poetry or novels).
On a more meta level: it has been pointed out that most depictions of office work in film center on getting ready for some "big presentation." Office work doesn't rely much on presentations, really — but film writers live or die by how well they present their story ideas.
Ruby Sparks: Calvin is a young novelist struggling with writer's block.
Seven Psychopaths: Marty is a struggling writer who dreams of finishing his screenplay "Seven Psychopaths".
Sleuth: One of the protagonists has become wealthy as a successful writer of popular, though now old-fashioned, crime fiction novels, which feature an aristocratic amateur detective, St. John Lord Merridew.
Before Sunset: Jesse has written a novel, This Time, inspired by his time with Celine, and the book has become an American bestseller.
The Help: Skeeter has just finished college and comes home with dreams of becoming a writer.
In a Lonely Place: The film starts out with Dixon being a down-on-his-luck screenwriter who has not had a hit "since before the war."
Basic Instinct: Catherine Tramell, the female lead, is a crime novelist. And a particularely manipulative and genre savvy one at that; by the end of the film it's revealed that she set up almost every event to emulate her own book.
Swimming Pool (2003): The story revolves around a middle-aged English mystery author, who is having writer's block that is impeding her next book.
Secret Window: The story is about a successful author suffering from writer's block and depression.
Breakfast at Tiffany's: The male lead is a writer who has not had anything published in five years since writing a book of vignettes titled Nine Lives.
The main character in Midnight in Paris is a writer trying to put the finishing touches on his novel.
If You Believe: Susan, the protagonist, is an editor working for a publishing house and Tom is a lawyer who gave up his career to become a writer. Susan ends up editing his first novel.
William Hurt's character in Smoke (1995) is a novelist who's career came to a hold after the tragic death of his wife. The character is named Paul Benjamin, a reference to the film's writer Paul Auster whose second forename is Benjamin.
Cabin By The Lake centers around a scriptwriter's problems to write a satisfying conclusion to his story... and is also a serial killer.
Ford Prefect's job as a writer for the eponymous Encyclopedia Exposita provides him with an excuse to go on his dangerously irresponsible adventures. His problems with his editors, who butchered a long, complex, beautifully-written article he spent fifteen years on into one word, are a major point in the series.
And Arthur Dent worked for the BBC. Take a guess at who Douglas worked for. This gets lampshaded in the Quandary Phase of the radio series, where Arthur's producer is played by the original producer of Hitchhiker's, Geoffrey Perkins. A significantly Downplayed Trope in this case, however: in the first volume of the novel this fact is confined to a single brief mention that he "worked in local radio" that never really comes up again afterwards, and indeed Adams never quite gets around to going into specifics, so Arthur could just as easily have been a sound engineer or even a presenter.
Richard Matheson's short story "Mad House" focuses on a writer with a nasty case of writer's block, among other problems.
In Adventures in Space and Time with Max Merriwell, the title character is an author who meets living avatars of his Pen Names on a cruise. The other characters all take a writing workshop with him. The character Pat Murphy (Pat Murphy often names characters after herself) writes a blog called The Bad Grrl's Guide to physics. Murphy is a science writer.
In Wild Girls, two twelve year old girls write a story together. When they win a writing contest, they get to take a writing workshop with the eccentric Vera Volante.
Allen Carpentier, the protagonist of Inferno, is a Speculative Fiction writer, just like Niven & Pournelle. In some ways Carpentier seems to represent Niven (more so than Pournelle), and expys of many other SF authors and other then famous personages appear in the story, but at the same time Carpentier's depiction is used to savage personal shortcomings that Niven himself might reasonably have.
Footfall features several sci-fi authors, including clear Author Avatar versions of both authors as well as one of Robert A. Heinlein, brought together by the government to help think up ways to fight an alien invasion.
Lucifer's Hammer (partly based on a scene from the first draft of Footfall that their editor demanded they expand into a novel in its own right) features writers and journalists among the Loads and Loads of Characters living through the collapse of civilization after a major comet impact.
The final chapter of The Number of the Beast is a huge cross-dimensional convention attended by sci-fi authors and characters from multiple fictional universes.
Quite a few of Stephen King's protagonists are also writers.
Misery: Paul Sheldon is the author of a best-selling series of Victorian-era romance novels surrounding the heroine character Misery Chastain. The antagonist, a fan of his books, doesn't want him to conclude the series and goes off the deep end.
The Dark Tower: He's written himself into the story (though not as the protagonist).
"Word Processor of the Gods" a short story in the collection Skeleton Crew
"The Ballad of the Flexible Bullet", also in Skeleton Crew: Reg Thorpe
The Tommyknockers: Roberta "Bobbi" Anderson, a writer of Westerns although it's a bit of a misdirection, as she actually becomes the first victim, and her friend Gard, a poet, steps in as the true protagonist.
"1408", short story in Everything's Eventual: Mike Enslin writes non-fiction books about haunted places.
The Shining: Jack Torrance is working on a play and has a pile of short stories under his belt.
Carrie: Sue Snell wrote a book about her experiences.
The Green Mile: Paul Edgecombe is the narrator, a main character, and also writes a huge portion of the book.
In Doctor Sleep, Chetta is a poet and her granddaughter's husband is a history professor taking a sabbatical to write a book.
The first book in the Legacy of the Aldenata series by John Ringo starts off with a clear Author Avatar sci-fi writer being called in as an expert by the government to help deal with the consequences of First Contact with aliens. A clear equivalent of David Weber is mentioned as being in the same group.
The World According To Garp. Garp's first two novels have plots that are similar to Irving's first two novels. In fact, a rejection letter Garp receives for one of his stories was one that Irving received in Real Life for the same story.
The narrator of Irving's The 158 Pound Marriage is a semi-successful author of historical fiction. The novel describes but also results from an author's frustrating, year-long research trip to Vienna, which yielded no intriguing fictional narratives but did yield a hot wife.
Taken Up to Eleven in A Widow For One Year. Ruth Cole, the protagonist, is a successful writer. Her father, who is a main character in both sections of the book, is a writer/illustrator of Not for Children children's books. Her long-lost mother writes detective fiction.
The main character in his novel Cat's Cradle is a writer who starts out doing research for a book he's planning to write about the day the first atomic bomb was dropped on Hiroshima. Later in the story, he takes an assignment from a magazine to visit the island of San Lorenzo and write an article on it, where he gets more than he bargained for.
Isadora Wing, the protagonist of Erica Jong's Fear Of Flying and its sequels, How to Save Your Own Life and Parachutes and Kisses. The Isadora character is loosely based on Jong, and the stories on her personal life. As well, Sappho's Leap is about the poet Sappho.
Jake Woods and Clarence Abernathy, respective protagonists of the first two books in a trilogy by Randy Alcorn, are both newspaper columnists.
In Jeff VanderMeer's Shriek: An Afterword the dual narrators are an ex-gallerist and an ex-historian respectively, and both earned their living for much of their lives as freelance writers of various essays and articles. Since the book is a fictional autobiography, the financial problems associated with the profession are often in the foreground.
In Greg Bear's science fiction novel Queen of Angels, the story revolves around a novelist, playwright and poet, who has just killed eight people. Another main character is also a writer.
Dean Koontz seems to be quite fond of this trope; to name just a few examples, the protagonist of his book Cold Fire is a reporter, and in Lightning, the main character is a novelist.
Henry Fitzroy, the vampire from Tanya Huff's Blood Books series (turned into the TV show Blood Ties), is a romance novelist. In the TV version, he writes and draws graphic novels.
Anne Shirley in Anneof Green Gables publishes various short stories that are published. Several times in the series people accuse her of writing friends and family into her stories. The Anne books are in many ways autobiographical with Anne's life reflecting many events in L. M. Montgomery's life including the deaths of her children.
In The Blue Castle has a mysterious writer who ends up with a close connection to the main characters.
A Tangled Web there is an unseen book writing lady that is mentioned. Some characters live in the hope that she will "write them into a story". Others live in terror of her doing exactly the same thing.
Emily, of the Emily of New Moon books, knows she not only wants to be a writer, she is a writer with all of her self. The people around her can use this need to manipulate her if they want — promising her that she can go to college, no strings attached, but only if she gives up writing fiction for the entire time. And in the third book, Dean Priest tells her that A Seller of Dreams is, basically, "cute," because he's jealous of her writing and wants her to give it up, even though he realizes it is an unfinished masterpiece.
William Goldman's The Color Of Light is about this trope. It goes a bit over the top in lampshading it, though.
Scheherazade gives the impression of being some Arab Coffeehouse bard's ideal woman.
Dr. Watson is, of course, a medical professional, but it's on account of his writings about Holmes that Holmes is so well known. Of course, the stories he writes that make Holmes famous are the same ones that we read, so this could be the world's first meta example of the trope.
Being one of the few doubled tropes on this page, Sir Arthur Conan Doyle was also a doctor. Naturally a doctor-writer would write about a doctor-writer.
Bram Stoker's Dracula goes even further. It's presented as a series of journal entries and articles compiled by Mina Harker, and the construction of the book itself assists the heroes in uncovering Dracula's secrets. So the writing of the book is actually a plot point within the book.
Judy Abbott, the heroine of Daddy-Long-Legs, goes to college specifically because of her writing. Her anonymous benefactor likes a funny essay she wrote about the orphanage where she grew up, and agrees to sponsor her education so she can become a writer.
The narrator in Nikos Kazantzakis's stunning novel Zorba The Greek is a writer, an attribute for which Zorba often pokes fun at him.
The narrator of the framing story in Life of Pi is an author who wrote a historical fiction novel that should technically have been amazing, but to him was so unlikely to raise any eyebrows in book publishing that he tossed the entire manuscript. Then at a café he met someone who told him about a young Indian man named Piscine...
In Vladimir Nabokov's Lolita, the narrator Humbert Humbert is a literature professor, and although he never refers to novels that he has actually published, he does tell Charlotte Haze that he was working on a novel when she finds some very suspect entries in his journal.
He is writing a rather large scholarly piece on the works of Rimbaud, Verlaine, and Baudelaire, which I believe is actually published early on into the novel. This is a common trope for Nabokov, at least for his English language novels; almost every one of them features some sort of writer as the protagonist. As we approach the end of his career, the number of similarities between this writer/protagonist is notably increased. Nabokov notes this, and frequently takes a poke at his protagonists for being shades of a more 'real' life.
According to legend, the implications that this trope presents almost led Nabokov to destroy his materials for Lolita, on the fear that people would think he was actually Humbert.
The lead of P. G. Wodehouse's Life Among the Chickens is a writer named James Garnet. Early in the story, he shares a train carriage with a pretty young woman who (unbeknownst to her) is reading his novel, and says to her father that she likes the protagonist. The following quote forces the reader to frown at the novel and go "hang a minute!"
"But I like Arthur," said Phyllis, and she smiled—the first time Garnet had seen her do so.
Garnet also smiled to himself. Arthur was the hero. He was a young writer. Ergo, Arthur was himself.
One of Hercule Poirot's friends in Third Girl is a middle-aged mystery-writing Englishwoman, much like Agatha Christie, who tries a spot of amateur detecting. And, in accordance with the tropes of the genre, is clonked over the head shortly thereafter.
Agatha Christie has several characters who are writers, including Ariadne Oliver and Miss Marple's nephew Raymond West, both of whom appear repeatedly in supporting roles throughout her stories.
The narrator-protagonist of The War of the Worlds is an academic author. H.G. Wells wrote a lot of non-fiction alongside his novels and short stories, though he is less-known for the former today.
The protagonist in Terry Pratchett's non-Discworld short story "Final Reward" is the author of a long-selling series of barbarian fantasy novels.
From the Discworld novels, William De Worde started off as a freelance letter writer, then later becomes a newspaper publisher and journalist in The Truth. Appropriate when one realizes that Pratchett was originally a journalist himself.
In Maskerade, Granny Weatherwax and Nanny Ogg travel to Ankh-Morpork after they learn Nanny's been cheated out of royalties from her risque cookbook. The throwaway gag about spelling "famine" with seven letters is a Shout-Out to the same error that occurred in Real Life.
In Snuff, Vimes has to meet with a famous children's book writer Miss Beedle. Walking up to her house, he muses that he has no idea what writers do at home. Possibly sit in their nightgown drinking champagne. A footnote remarks that this is completely true.
The protagonist of The Chronicles of Thomas Covenant is a successful writer whose life quickly turns to shit. When things start getting better, he refuses to believe it is real...
French author Bernard Werber loves to put writers as characters: journalists and novelists are all over the place, it seems.
British author and cartoonist Ros Asquith has done this several times. Letty in the Teenage Worrier series (although her dream is to become a film director, she frequently mentions that she is a published author as well), Cordelia in the Girl Writer series and Flowkwee in Letters From an Alien Schoolboy are all examples.
An egregious example is Jonathan Franzen's Freedom, whose story is largely told from the perspective of Patty Berglund writing her autobiography. Even though Patty knows she isn't too smart and otherwise shies away from intellectual life, she seems to write about as well as Jonathan Franzen does in the rest of the novel.
House of Leaves is a more indirect use of this trope. To quote the quote on its page, "It's a book about a book about a film about a house that is a labyrinth."
Betsy in the Betsy-Tacy series is all about telling stories in the early books, then naturally progresses to a writer as she grows older. She shares her passion for writing with her future husband. This makes sense, as Betsy was basically an [[Expy]] of the writer Maud Hart Lovelace, who was also married to another passionate writer.
The narrator-protagonist of Carol Shields's Unless is a writer and translator.
In The Book of Joe, the protagonist is Joe Goffman, a successful author struggling with his writer's block.
In Fame, there's only a single character in the entire novel who doesn't see himself as a writer or character. The rest of the cast consists of three writers, a forum addict, a number of fictional characters, a world famous actor, a man who invents his own new life, and a woman who ends up as a fictional character against her will.
Lord Peter Wimsey's love interest Harriet Vane is a mystery writer. And that's not the only similarity between her and Dorothy Sayers.
Wonder Boys — both novel and film — is about an English professor who is stuck in the middle of writing an endless, soul-sucking Door Stopper of a novel.
Charlie Bucktin, the main (but not titular) character of Craig Silvey's Jasper Jones, is an aspiring author. And so is his dad.
Tosca Lee's Demon A Memoir is premised around not one, but two main characters as writers: one, an editor who has tried and failed for years to write novels, and second, a demon with a marvelous storytelling gift but no ability to physically write and publish his story. Hence, a partnership (of sorts?) is born.…
Kill time or die trying: being based on real events most of which the authors were present, features the authors themselves as characters. Subverted, in that the fact their being writers is barely mentioned, apparently to avoid spoiling the fun of trying to figure out which characters are the authors.
McEvoy in the Michael Connelly novels The Poet and The Scarecrow is a journalist just as Michael Connelly was before becoming a mystery writer. Said reporter ends up uncovering serial killers in both stories.
A very literal example of this trope, Stephen Glass, former journalist for The New Republic and who is most well-known for partially or wholly fabricating many of his stories, went on to write a semi-fictional novel about a journalist who is caught fabricating his stories.
Ben Mason was a poet before he was turned into a zombie.
Meg in This Tragic Universe, by Scarlett Thomas, is a Starving Artist paying the bills (just) with ghostwritten genre fiction while trying to write a "proper" novel which has gone through multiple rewrites over several years. (And yes, she's contemplating adultery).
In many a Chivalric Romance, the narrator praises generosity to minstrels, and the porter — who, being in charge of the door, could keep ministrels out — is often the Butt Monkey of the tale.
Tom Holt has two in My Hero!; the protagonist is a writer of Thud and Blunder adventure stories, and the second is a mysteriously-vanished western writer who has gotten Trapped in TV Land, and needs the help of the first to escape from the story.
In the new All Souls Trilogy, the main character Diana Bishop is a historian (with a specialty in Alchemic Texts) who just so happens to be a witch, an extremely powerful one, who pretty much holds the fate of the three creature races — witch, deamon and vampire — and maybe the world in her hands. The author, Deborah Harkness, is also a historian — this is her first fiction work. Taking that into account, we can see Harkness having the same reaction to Matthew Clairmont, a vampire; he's about fifteen hundred years old? THINK OF THE HISTORY HE'S LIVED THROUGH!!
The Mervyn Stone series by Nev Fountain. Whodunnits about the former script editor of a cancelled sci-fi series by a playwright and Doctor Who audio-drama writer.
In The Master and Margarita, the Master is a writer of a particularly un-Soviet persuasion, just like the author himself. And many antagonists / victims of demonic pranks are politically motivated literary critics, the same sort of people who made Bulgakov's life miserable.
In The Trail of Cthulhu, four of the six protagonists have professions relatives to writer. Shrewsbury, Clairborne Boyd, and Horvath Blayne are scientists focused on humanities (the former about occultism, the two latter about ethnology), Nayland Colum is a novelist. Indirectly, Andrew Phelan have been hired by Shrewsbury because he has some skills in a secretary job, among other things. The less relevant protagonist to this trope is Abel Keane, who is a theology student aiming to become a priest.
The father in Helen Cresswell's Bagthorpe Saga is a scriptwriter.
The narrator's father in Jean Robinson's The Strange But Wonderful Cosmic Awareness of Duffy Moon writes a cooking column under the name Grace Gallagher.
Yuri Zhivago of Doctor Zhivago is an aspiring poet and novelist, something he seems to have been inspired to do by his uncle, Kolya Vedenyapin. Indeed, the third main plotline concerning his life, alongside his love life and his struggles in the midst of the Russian Revolution, is his striving to become a renowned writer.
While not the main character, McGee of NCIS is a popular novelist on the side, writing thinly veiled accounts of his adventures with the Gibbs Team.
Temperance Brennan of Bones is a forensic anthropologist who also uses her professional expertise to write books based on a "fictional" forensic anthropologist named Kathy Reichs — who is the real life author of the books upon which the show is based.
What's also interesting in her case is that, she honestly thinks her books are best-sellers because people are actually interested in the forensic science — not, you know, the human interactions and crimes that facilitate said forensics. She is bewildered and annoyed when being interviewed about her latest book, all the reporter wants to talk about are the characters and motives instead of how interesting and true to life her science is.
We find out later that, had she her way, she would forgo the human interactions and focus only on the crime/science if she could; her publisher/editor/agent/whoever said it wouldn't sell, so she felt compelled to add the rest. Said "rest" comes heavily supplied by help from Angela, including several sexual positions and/or techniques.
And there is no evidence that she is wrong in her thinking, given how popular well written hard Speculative Fiction tends to be. This is almost an aversion — a scientist writing as a scientist being forced by writers to write like a writer.
The protagonist of Castle writes mystery novels for a living, and because of his connections, he gets to spend a lot of time with the police, getting inspiration while offering his own professional insight. And if that wasn't enough, he writes about a writer who follows the NYPD around.
The two main characters of Spaced are Tim, an artist who wants to write his own comic book, and Daisy, a print author with no ideas.
In Just Shoot Me!, everyone works for a magazine. The only one in the main cast who is a writer by profession is Maya, although Dennis has shown some writing prowess, penning (among other things) at least two screenplays, a few songs, an advice column, and most of his boss's "autobiography".
Canadian channel TVO used to run a program called Write On, which offered grammar lessons as short TV sketches. Yes, it's about as strange as it sounds, but the characters were journalists. You can view an episode here
Dennis Potter was a writer who suffered from severe psoriatic arthritis. His best known work was the TV Series (later made into a movie) The Singing Detective, about a writer who suffers from psoriatic arthritis. A difference is that the writer in the TV series wrote pulp detective fiction, while Potter mostly wrote rather surreal TV series.
The Five-Man Band in How I Met Your Mother aren't writers by trade, but they do enjoy spending hours brainstorming sit-com joke lines. On top of that, Barney is a popular blogger, Marshall writes songs as a hobby, and Ted and Barney compose dueling poems in The Sexless Innkeeper.
Ted may be an architect, but he does love to wax douchey about literature and poetry.
During his retirement from the FBI, David Rossi of Criminal Minds supported himself as an author and lecturer. Although he is a nonfiction writer similar to the real life profiler John Douglas.
Similarly, Ryan Hardy of The Following became a non-fiction author after being forced to retire from the FBI due to his injury.
The main protagonist of the show Bored to Death is a struggling writer who even has the same name as the creator of the show (Jonathan Ames).
Jerry on Seinfeld is, like his Real Life counterpart, a comedian; many episodes show Jerry struggling to write new material for his act. When, in the episode "The Pitch", he and George pitch a "show about nothing" to NBC execs, this is a direct parody of the creation of the show by the real Jerry and Larry David.
Gabrielle from Xena: Warrior Princess may not have been a writer in the same way the others are, but as a bard and chronicler of Xena's adventures, it's probably as close as we get. There's even an episode about her writing a story about Xena. Virgil, Joxer's son, is a poet, much like his real life namesake.
The first season of Mad Men revealed that most of the men in Sterling-Cooper have secret novels or plays they are working on. When one of them manages to get his short story published, he earns the immediate envy and respect of everyone else in the office.
Kip and Henry from Bosom Buddies worked in advertising. Henry was a copywriter (and Kip an artist). Henry believed their experiences living in drag would "make a great book."
A sideplot in the Star Trek: Deep Space Nine episode "Shadowplay" has Ben Sisko's son Jake trying to work up the courage to tell his father he wants to be a writer instead of joining Starfleet. Ben accepts this once Jake finally tells him, and Jake starts working as a journalist and writing short stories and novels in his spare time by about the middle of the series.
In Mama ist Unmöglich, Mama is a popular mystery writer. She has friends in the police and sometimes runs into fans as well.
Trixie True Teen Detective has Joe Sneed, a writer who wants to write hard-boiled detective novels, but is stuck working in a syndicate stable writing perky-girl-detective stories instead.
The Musical of Little Women uses this, of course, following the book, but it's amusingly evident when Jo, in the song "Weekly Volcano Press," supposedly reading aloud her story, reads something that sounds more like a script for a musical ("The forest is dark and spooky. Clarissa enters, her clothes in disarray...") than a past-tense short story normally would.
Mark from Rent is a would be film maker who has written a few screenplays. (Which he burns.) His friend Roger spends the musical singing about how he wants to write a song.
Cliff Bradshaw in Cabaret — naturally enough, because the show ultimately derives from novelist Christopher Isherwood's memoirs kept while he was living in Weimar Berlin.
Jon Arbuckle of Garfield was specifically identified as a cartoonist in early strips, at least before he essentially became a full time Cloud Cuckoolander loser guy. In the cartoon, however, his profession regularly drives the conflict in the plot.
Sydney in Dykes To Watch Out For is an academic writer and there have been other minor characters like Deidre and Anjlai who write but main character and semi-Author Avatar Mo has creator Alison Bechdel's bibliophile tendencies instead of being a writer herself.
Theater in general falls into the same trope. Many plays are written about writing or staging a play.
The game also has a more direct invocation of this trope by having a character that's game developer (who's in an insane asylum... with some pretty fun dialog). Interestingly, this happens very rarely in video games which seems to imply that video games seem to be one of the media that bucks the trend. Why this is is another question.
The books Alan is famous for are noir-inspired crime thrillers that are basically Max Payne, Remedy's previous series. They even have the same voice-actor playing the character during voice-over "excerpts" of the books. A reader of Alan's says he's "a little heavy on the metaphors", which is the previous' games best known feature.
Harry Mason from Silent Hill. Possibly not a very good one.
Adrienne Delaney from Phantasmagoria is a best-selling novelist, particularly well known for her book Blue Moon Rising.
The protagonist of Scratches, Michael Arthate, is rising horror writer; In Last Visit the protagonist is an unnamed reporter.
Segagaga is about running SEGA as a company, producing and distributing games. Played with, however, as the characters in the company's games are real and help with development (Amigo from Samba de Amigo is a high-level programmer, for instance), the development process itself plays out like a normal video game, and past SEGA systems are actually spaceship-like weapons.
Interestingly, Catherine is a video-game where the protagonist is a video-game designer.
The main character in Manor Memoirs is a writer having difficulties with her latest book.
The title character in the Dana Knightstone series is a historical novelist.
Slick from Sinfest is sometimes seen trying to write a literary masterpiece. He also does poetry slams in the earlier strips.
Davan of Something Positive is, for a time, the writer of a webcomic. He also has a regular job as the personal assistant of a theatrical producer; this job on occasion makes use of his writing skills, such as when he had to rewrite a show's script.
Andy French of Mission Hill works at a mattress store, but he's an aspiring cartoonist. At least one episode deals with his discouragement over all the rejections he's gotten sending his comics to various magazines.
Ginger Foutley of As Told by Ginger was a writer. The show specified that she was a gifted poet, but it was inferred that she was an all-around talented writer.