Well I feel that porterz has the upper hand in many ways and will win this dispute very easily to his satisfaction.
How did you pay? credit card? dispute it and let the credit card company chew on them a bit.
I wonder if EBAY would step in and help (I doubt it) but I thought they had some vehicle purchase protection crap.
http://pages.motors.ebay.com/buy/pur...ion/index.html