I've run across these or similar east european types running their vehicle scams in Utah like you describe. Not surprising to hear they are still at it.

The best place to report it is the MVED:

http://mved.utah.gov/

They have the ability and power to go chase down people like this. Although they are hard to catch. But they can actually put them in jail if they can build a case and get them arrested.

There are crooked car dealers and individuals selling cars illegally so it's buyer beware. There are already warnings about the flood damaged cars that will be pouring into Utah to be sold to the unwary. It happens every time. They clean them up to disguise the damage and rip people off.

Know who you are dealing with and the history of the car when making a purchase. craigslist is a poor place to shop for anything much less a car.