You need to prove the car meets US DOT and EPA regulations, if it doesn't sayes so on the car, you would have to contact VWoA and ask them if it does. If it does, most new cars do, have them send you a letter saying the vehicle meets these standards.
When you bring the car to the US, you have to pay a fee of 2.5% of the market value or the price you payed to customs. They should give you a form you have to show the DMV. That should be it.
Anyway, call VWoA.