You actually sent someone on Craigslist a check? I've driven a couple hours to pick stuff up on CL and a couple months ago I had a guy drive 4 hours to pick something up from me (it was on the way to a friends house so it sort of made sense).
Rules for Craigslist are:
cash only
Meet in a public place
Carry your 9 inside your waistband or a 38 or 380 in the same pocket as your wallet.
Follow these simple rules and you won't get ripped off again.

Sucks but its the nature of the beast. If the check has been cashed and you have emails outlining the terms you may able to get the PD to help you out.