I had that exact same thing happen to me!! About a yr ago, i was parked at the grocery store and came out to my car. I had like 3 people come up to me, and tell me that someone driving a toyota pickup truck, hit my car (rear bumper), and took off. Luckily, someone got the license plate of the @$$hole. So, the police hunted him down. It was only a few scratches on my bumper, but I got an... ahkhummm... estimate for $1200. lol, i made that fukker pay, he wanted to settle without insurance companies, so I got cash!!!
I hope you're able to track down the friggen morons, ...you can't have anything nice these days huh... Also, I just found a damn door ding on my passenger door, I'm friggen pissed now. I might be able to get out with that paintless repair, i hope....