Discworld played with this in the book Maskerade, where two performers at the opera were competing for attention in the middle of a crisis. One is a major side character, who's looking to replace the other, older performer. At the first sign of trouble, she emits a little sigh, does that movie-swoon that ensures a pain free landing. Upon revival, she looks around baffled and asks, "Where am I?". The other also fainted, but because everyone was paying attention to the other singer was forced to revive herself and faint again several times before eventually resorting to hysterics.
The titular murder victim at center of James Ellroy's The Black Dahlia is characterized as the epitome of this trope (and pays the price for it).
Carmelita Spats from A Series of Unfortunate Events. As well as Esmé Squalor and to some extent, Count Olaf. Naturally, Carmelita is adopted by Esme and Count Olaf in book eleven and thought of as "the daughter she never had".
Gilderoy Lockhart from the Harry Potter series. Even after he accidentally erased his own memory with Ron's broken wand he still thinks people want his autograph. Why? "I suspect it is simply my good looks!"
The staff of the hospital seem to think Lockhart's penchant for autographs means he's recovering. That said, he's vaguely aware that some people think he's a big deal, he just has no idea why that might be. But he likes the attention (another good sign, according to the healers), so he doesn't really let it cost him any sleep.
The Ministry of Magic also forces the newspapers to portray Harry as this after the events of Goblet of Fire.
Mary as well, though she has more of an excuse. She's the least beautiful of the sisters, tries to be "accomplished" to make up for it, and thus never passes up an opportunity to show of her "accomplishments."
The Idiot: Ippolit Terentyev seems to be constantly seeking attention. Other characters think his main motivation is bitterness over the fact that other people can be happy while he's dying of tuberculosis. At one point, he interrupts a party in order to read aloud a letter he wrote—which turns out to be a suicide note. Upon finishing, he grabs a gun, points it as his head, and pulls the trigger. The gun doesn't fire and Ippolit is unhurt, which just leads more people to assume that he deliberately loaded the gun incorrectly, and that the entire incident was just a cry for attention.
Misty Carpenter from The Identity Matrix is a literal attention whore: She's a prostitute who becomes a stripper to get more attention, better tips and an upgrade in her johns. She was programmed to be this way by a Government Conspiracy, who "thoughtfully" threw in nymphomania as well on the theory that it's not really a punishment if she enjoys it.
In the final book of the Uglies series, Extras, many, many teenagers have become this, because the 1000 most popular Faces have unlimited resources. Everyone else has strict limits on the resources they can use.
Discussed by British secretary of state Lord Chesterfield in the Letters to His Son: "They are always the heroes of their own fables; and think that they gain consideration, or at least present attention, by it. Whereas, in truth, all that they get is ridicule and contempt, not without a good degree of distrust; for one must naturally conclude, that he who will tell any lie from idle vanity, will not scruple telling a greater for interest."
In The Hitch Hikers Guide To The Galaxy, Hard Drinking Party Frood Zaphod Beeblebrox managed to become President of the Galaxy because of how extreme and outrageous his constant attention-seeking is, a position that involves almost no actual politics (although he is eventually revealed to have been the one to have ordered the destruction of the Earth) and a great deal of Gargle Blaster-drinking and socialising, and serves only to distract the population of the Galaxy from asking who really is in charge. He reveals some Hidden Depths, though, not least a Neuro-Vault.