Lola of the Barry Manilow song "Copacabana". Though to be fair to Lola, she pretty much had a mental break after the love of her life was killed in front of her and spends her days drunk and grieving after that.
Metallica's song "The Memory Remains" is about an unnamed actress past her prime. Especially poignant since they managed to have 1960s starlet Marianne Faithfull on backing vocals for the song and appear in the video. Talk about hitting close to home...
"Yesterday's Hero" by John Paul Young.
Bucks Fizz's (never spoonerise that name) Golden Days and Now Those Days Are Gone seem to be about this trope.
Dog Fashion Disco wrote a rather creepy song, "Plastic Surgeons", that is a plastic surgeon's serenade to his white dwarf starlet clients.
Would you like a new face to face a new day? It seems the mirror is your worst enemy For I am Christ to the shallow and aging A plastic surgeon to the stars of old
Prefab Sprout's "The King of Rock And Roll" is about a one-hit wonder who becomes one of these. It was their only hit... in the US.
Faith Hill's "When The Lights Go Down", dedicates a verse to this phenomenon.
So another star falls from the Hollywood Hills without a sound, when the lights go down.
"Mr. Richland's Favorite Song" by Harry Nilsson, about a (male) teen idol who goes from the heights of fame to being "a fallen star who works in a bar where yesterday is king."
"New Age" by the Velvet Underground is about a love affair between a "fat, blonde actress" and one of her fans.
"Della Brown" by Queensrÿche tells the story of a middle-aged homeless woman who was once a great beauty that had the world at her feet and her pick of men. Once her beauty faded, she was cast aside and had to live on the street because she had no other means of supporting herself other than with her looks. The song ends with her waiting for a man to come along and make her happy again.
"Duchess" by Genesis depicts a starlet for whom "everybody cried for more" lose popularity with her fans, to the point where "nobody (cries) for more".
Krayzie Bone's "What Would You Do?" tells the story of a washed up rapper who returns back to the life of crime with disastrous consequences.
"Paperitähdet" (Paper Stars) by Finnish rock artist Juice Leskinen.
"The Lucky One" by Taylor Swift is about an aspiring actress who went to Hollywood seeking fortune and fame, but ended up as one of these when she realized that said fortune and fame weren't what they were cracked up to be. It has a Happy Ending though: She uses her money to buy a big plot of land and retire to a quieter, simpler, life.
Two male examples show up in country music, with Tanya Tucker singing "King of Country Music" and John Anderson doing "Would You Catch a Falling Star?"