the compressor comes on but it wont stay on, and the air doesnt get cold at all, but it has full freon in it, is there a good place to buy a new air compressor at?

Compressors are not cheap, you really should determine why the compressor does not stay on. How do you know the system is full of R-12 (DuPont trade name is Freon)? If you have a large leak and just filled the system, it may have all leaked out already. Are you sure it is not overcharged? If overcharged, it could your symptoms too. If your pressure switch is faulty or improperly adjusted, it could cause your symptoms. If the compressor clutch is bad, it could possibly cause your symptoms.

Starting by replacing the most expensive component is not the proper way to go. Since you'll need to have the R-12 removed by a certified shop to replace the compressor anyway, it would seem reasonable to have a certified shop properly diagnose the system by checking pressures and inspecting for any leaks.