If you did not purchase comprehensive coverage you are out of luck. I'm no lawyer but I suppose you could sue the parents of the juveniles who stole your vehicle. Good Luck!
The thief who stole the car is the responsibile party. If you have full coverage though you should have no problem getting the loss covered.
Call the police.
If you have a stolen template on your vehicle you may get pulled over by the police. You need to have that corrected.
YOU are responsible for the debt that is secured by the "stolen" car. Be sure to make a police report on the 'stolen" car.
If you know the registration number of this vehicle, you can check easily by performing a online police stolen car check by paying a little money.
In most cases, these investigations open when the owner of the vehicle reports it as stolen.
The police can hold you for as long as they deem necessary if you have broken the law and driven a vehicle with a stolen template. Every state is different.
If impound was caused by your vehicle parked illegally, then the impound lot or the towing company could be held responsible. If it was impounded because it was retrieved as a stolen vehicle, then no one can be held responsible. However, in both cases, the personal belongings in the vehicle can be covered by either your own auto insurance under the Comprehensive portion of your policy or by your own homeowners/renters insurance under the Personal Property portion of your policy. They are subject to your deductible/s.
Assuming the stolen car was insured, the stolen cars insurance would be responsible. If the stolen car was not insured, the driver, if located would be responsible. If not located then the owner would probably be held responsible. Hopefully the struck vehicle is insured for "uninsured motorist" coverage. Filing the report after the accident would document the theft, but not neccesarily clear the owner of responsibility.
You or your insurance company. The owner of the stolen vehicle would not be responsible because their vehicle was stolen and the driver of the stolen vehicle's insurance would not cover it because he was driving a vehicle that was not on his policy and he did not have permission to drive.
Report it stolen to the police.
If you have found your stolen vehicle at a salvage yard, you need to call the police immediately. Automobile theft and receiving stolen goods are both criminal offenses.
If you are stopped by the police for having a stolen template on your vehicle you will need to properly register and insure the vehicle with valid, legal plates and show the paperwork to the court.