There are a mind-blowing 3.5 million cars sitting on dealership lots going unsold. That's the most ever and car makers are looking at two very unappealing options. Both Ford and GM might have to shut down plants if the glut of vehicles continues. But other companies like Chrysler seem to be doing fine. Incentives might rise even higher as well with most GM trucks already at $5,000. If there was ever a time to buy an American car this seems to be it.