Charles Bukowski

You might want to read those authors whom Bukowski most admired (and many of whom are my favorites as well):

Ernest Hemingway (specifically his early short stories)
Louis Ferdinand Celine (specifically _Journey_--I don't think Bukowski liked much of his later work, although I do)
John Fante (specifically those novels "starring" Arturo Bandini)
Knut Hamsun (specifically _Hunger_; incidently, Knut is my favorite writer of fiction)
Fyodor Dostoevsky (as has been said by men wiser than myself, in _Notes From Underground_ one can "hear the voice of blood")
D.H. Lawrence

As for poets, I guess Ezra Pound ranks near the top, as does Robinson Jeffers.

Though I doubt Bukowski was familiar with him, some of my favorite writings are the "autobiographical fiction" of August Strindberg (_Inferno_, _Alone_, _Son of a Servant_, etc.)