Nightmare....now is the time to show your strength.....
My advice:
Check all of the safety sritical stuff on your car.....brakes, wheel nuts steering, fuel, exhaust security electrix etc
If all is OK there Fit New Budget tyres
Wash the car THOROUGHLY
Clear laqure over everywhere that got splashed (to protect the metal), but lets everybody see the extent of the damage
Create a new email address, PO Box, and/or pay as you go handset number (set it to silent, turn the answering machine on it on...DON'T record a personal message and never answer it)
Use a 'neutral, feminine but distinctive' email address eg "
[email protected]" (not that one though)
Print a few INFORMATION WANTED - THE ABOVE CONTACT INFO posters and put them in the back windows of your car with photos of the original damage
Then keep driving it around as it is.
You will start receiving info soon enough
Beware, some info will be lies, some info will be truth, some info will be threating
Keep records of EVERYTHING
Good luck
<EDIT:> don't offer a reward....and never return any communications...ever