Know how you feel mate, had my GTI keyed from wing to boot. I know who did it, but can't prove it. No use doing anything to the idiot/weirdo, as he has no job, girlfriend, friends, house and a owns a crap car. Just really frustrating.
Anyway, luckily the scratch was only in the laquer. Got a friend to buff it out with very fine cutting paste, then apply coats of wax. Got away with it this time, but it scares the sh*t out of ya!