If at all possible, deal with it yourself. But, seeing that he has done this sort of thing in the past, file a police report and go all the way through with it. If you don't someone else (will) get scammed and he will continue to do so as long as he isn't pursued through legal action. Most criminals don't turn a new leaf till then, most "get off" from the act, so do everyone a favor, it's your right and duty as an American.
(EDIT) Ok, that last bit sounded awful

but if a thief is among us, not just the AP community, everyone deserves to know