Which ones did you read so far? I'm guessing you've read the Godfather, so I'll recommend you the Sicilian if you want to read a little more about Michael Corleone's character and his extended stay in Sicily. If you want to break out of the Puzo norm (i.e. gangster novels), then I suggest you find the Fourth K. Picked it up at the library and it is pretty damned good so far.

A= Statement B is true
B= Statement A is false