So many shit books are written by masters students about the tribulations of being a writer, but very few ever, EVER hit the mark. It's like Natasha Beddingfield writing songs about writing songs - it's poo.
BUT some books and films spring to mind, where the film is about someone making films or the book is about writing for a living.
Sherwood Anderson's Winesburg Ohio = win (although he's a journo in this). Fantastic style and engrossing snippets of lives that are good short stories in their own right.
Fante's Bandini stories = win. Arturo is the essential dickhead writer who believes in himself so beautifully it's enraging.
Bukowski = WIN. It can never be done again (ever, and when people try they come out as gigantic cunts), but he produced some of the best books about being a beat-generation writer EVER.
Films I struggle with. Adaptation springs immediately to mind. Anything else?