The new one WHITEY, which somebody else mentioned above is hands down the best. All the others written by ex colleagues and enemies all sound the same after a while!!
I think that Howie Carr has written separate books on the Bulgers, Martarano, and Flemmi. While I haven't read the Flemmi book, I would swear that he told the same stories in all of the books. Total money grabs if you ask me.
Now Kevin Weeks is writing a 'fictional' book on Whitey?! Why do you need fiction when you were there and lived it? I won't give a dollar to help that murderer.
