Do you want to block foreign bidders? Just certain USA areas of the country?

eBay will let the bidder calculate shipping for his address if that's what you are trying to do.

You can also block bidders by eBay ID, and indicate no shipments out of the USA.

I posted a couple of SELLs yesterday and the listing process is different that it was earlier this year. I guess it has been simplified. Some of the seller options are not obvious, but I believe you can still put on the restrictions I indicated above.