Where is the selling price for Corvettes the cheapest in the U.S.?

nowhere.

Corvette prices are something to shop for. There is no particular place to buy them cheap. It will take alot of research, it also depands on what you are looking for year, options ect....? I will tell you one thing the best deals are from the private seller and do not buy from auto lots with the inflated prices. Dealers for the most part just want to make as much money on the car as possible, plus they do not know the history of the car, could be a salvage title which you do not want to deal with.