Vehicle templating is more what you're looking for I think.
The Bad Wrap 2007
Bad Wrap offers templating primarily for wraps done with Photoshop, and is mostly newer vehicles.
http://www.mr-clipart.com/
Mr. Clipart has many vector graphics and has added vehicle vector templates too, I seem to recall some folks saying the templates were slightly off.
The other way to go is template a vehicle yourself with the appropriate measurements and photographs.