I've caught Tony D at several of the major cons and I always make room in my schedule to play at one of his demos or to drop by and watch one in progress. His style and presence at the table are tremendous and both permeate his book.
I was pumped to be able to finally get my own copy at Origins 05 and our group has played several of the adventures that he provides for free on his website
Complete Mafia for D20.
If you find Tony D at your con, sit in and play a demo. You might just find yourself buying a copy, if you know what's good for you. You know what I mean?