A salvage title can only be issued by an insurance company (or unless someone wants it done at the DMV.) If the car was wrecked and no insurance was involved (like say on a track or by a really, really wealthy person
A perfect example HERE ) there would be no reason to notifiy the insurance company, hense no salvage history.
Carfax is a good start and it will list prior salavge, but its not 100%. in fact its more like 60%.
I'm currently doing the best I can to log all damaged cars, and once the IVR is fully fucntional it will be priceless, but the best place to check a car is still here on the boards. The more information you can give us the better off you'll be...