On my crashed laptop I had about 20 emergency/law enforcement vehicles ranging from cop cars, SUV's, bikes tow trucks, fire and Rescue to hummers and helicopters all found on Googles trimble warehouse. Just rebuild me a new PC so will be googling for them again as I lost them all I was also doing a police station. You will find a lot of police cars on google the only thing I didn't get was actual police officers in uniform though. Good luck in your search