In case you missed David Horowitz's Cliff Notes on Alinsky, here is the link with links to Parts 1-V.
"Saul Alinsky came of age in the 1930s as a Communist fellow-traveler (as his biographer Sanford Horwitt tells us in Let Them Call Me Rebel), but his real social milieu was the world of the Chicago mobsters to whom he was drawn professionally as a sociologist. In particular he sought out and became a social intimate of the Capone gang and of Capone enforcer Frank Nitti who headed the gang when Capone was sent to prison in 1931. Later Alinsky said, “[Nitti] took me under his wing. I called him the Professor and I became his student.” (p. 20) While Alinsky was not oblivious to the fact that criminals were dangerous, like a good leftist he held “society” — and capitalist society in particular — responsible for creating them."
Post-modern leftism: Alinsky, Beck, Satan and Me, Part V NewsReal Blog