Although you mention no CCTV in the actual carpark where you left your car, were there any in the vicinity that might have captured the f***** (censored by me) leaving the carpark with a nice stripe of your paintwork down the side of their car? There is CCTV everywhere nowadays

the offender is bound to have been caught somewhere. Maybe put some notices up in the carpark saying "did you see anything? £10,000 reward for information call 07xxxxxxx".
I'm so p***** off hearing about accidents caused by people's inability to drive properly. I find it totally sh !t that we live in a society where some daft moronic stupid twerp can only manage to exhibit the kind of skill and co-ordination of an out of control firework by using other cars to guide him or her around a carpark and then to leave the scene of an accident of their own causing with not even so much as a note saying sorry. It's a weird feeling when it happens to you, well it was for me anyway. I just wanted to keep driving around until I caught the b******* that did it and bring him/her to justice. It's a mix of 6 parts rage, 2 parts anger and 1 part disbelief, with a little pinch of worry that leaves a nasty taste in your mouth whenever you park your car next time.
It's happened to me on 3 occasions and has probably cost me over £100 in repairs each time that someone else should have paid for.
Sorry if I'm a little angry but I had to go to work all weekend, I've run out of beer and I've got to be in work again at 7:00am tomorrow. Better get to bed!