If you decide that the power window motor is bad (which is very common), be sure to inspect the faulty motor. If you take it apart, you may find that there are 3 disintegrated nylon plugs that have deteriorated between the plastic gear and drive gear. If they have gone bad, you can replace them with new plugs found at NAPA (about $8. I think they are only listed for fords, but they aren't rocket science. They can be trimmed to fit) instead of spending $50 on a new motor.
These plugs are found on power window motors and headlight motors (older pontiacs).