For me it is:
F Scott Fitzgerald: his short stories (ie: Diamond as Big as the Ritz, Bernice Bobs Her Hair, the Baby Party), the Crackup, the Great Gatsby, along with Tender is the Night.
As an actor, in my younger days, I read many plays, Shakespeare was ok, but Moliere was mind blowing, the invisible Invalid...... wow way ahead of it's time.
Woody Allen The Insanity Defense: The Complete Prose
Then there were the biographies that influenced me,
Zelda: A Biography by Nancy Milford the story of F Scott's wife Zelda Sayre
Kink by Dave Davies, talking about the founding of the Kinks in Dave's perspective
X-Ray the Unauthorized Autobiography by Ray Davies Early history of the KINKS told in a somewhat Orwellian style.
Stone Alone by Bill Wyman his story of the Rolling Stones
Brian Jones' biography Brian Jones: The Untold Life and Mysterious Death of a Rock Legend by Laura Jackson
Albert Goldman The Lives of John Lennon: in which the author gives John a very rough time making him sound mean-spirited, doing whatever he can get away with to tear down the subject even if it means passing off rumors as fact, speculating on the flimsiest of evidence, and using obscuring resources to the point that you're hard-pressed to know what to believe.
The books that got me into D&D while in high school:
JRR Tolkein of course with the Hobbit and Silmarillion
Gary Gygax's work
of course the classic every high schooler has probably read at some point:
Go Ask Alice and the obscure male version Jay's Journal
Among other books in the topic of counselling addiction, the Hardy Boys series and Encyclopia Brown series in 4th,5th and 6th grades (where I could read 1 a day because they were all basically the same), the Hitchhiker's Guide series, Mad magazine books like Don Martin Digs Deeper.