You have been more patient than anyone else would be. I can't believe that the last photos they posted for your build was all the way back in September. If you go to /r/cars - For Car Enthusiasts you should be able to start a thread there and ask for advice. The forum is very helpful, they should at least be able to help point you in the right direction.

EDIT: Here's another link to help http://www.reddit.com/r/legaladvice . I think you should get a lawyer now to start coordinating the return of your car otherwise it's going to be 2 weeks, and another "2 weeks"

Disclaimer: I am a comm guy for the Air Force and have very little legal knowledge.