The Treasure of the Sierra Madre, by B. Traven (TPB, 1963 edition of book first published in 1935, $2.25)
I knew about the John Houston movie with Humphrey Bogart which won 3 Academy Awards in 1949. What I did not know was the mystery around the identity of the book's author. No one really knows even now who he was, but it is not for lack of trying. The author wrote, "The creative person should have no other biography than his works.", and as far as Traven was concerned, that was that.
What is known is that the author was a good writer, who knew a lot about Mexico and its indigenous people, and that he wrote 12 novels. He was also (probably) German, and almost certainly either a communist or anarchist. His books definitely blame capitalism for the poverty and suffering of the Mexican people.
If you want to read all about the mystery, all you have to do is "google" B. Traven. Two of the more outlandish theories state Traven could have been either Kaiser Wilhelm II's illegitimate son, or else Jack London, who did not really commit suicide, just moved to Mexico. What ever you believe is true, reading this classic just got a lot more interesting. Look for it on the new fiction table.