How will you deal with these people…?

Rather than trying to define a target market by requirements, you can do so by simply deciding that you want to limit the geographical reach of your business. For example, if you are running a US – based business, then you might decide only to deal with US citizens so that you always get paid in dollars.
However, to some extent this defeats the object of setting up an e-commerce site that otherwise has access to a truly global marketplace. It is also a very narrow view – how do you know whether your best customers are likely to be US citizens, when it could be people in the UK, Australia or mainland Europe, for example?
Dealing with customers overseas raises additional questions, such as how are your overseas customers going to pay you, and once they have done so, how are you going to ship their goods to them?
However, these are not major considerations, because there are plenty of solutions available already, and there are more solutions coming to the net every day.
For example, most US banks will accept credit card charges from overseas, and online payment processing companies like Paypal and 2CO operate on a pan-global scale without restrictions.
Furthermore, most e-commerce sites use an online shopping cart to make buying a more convenient experience for customers, generally integrated with a suitable merchant account. This is something that we will look at in a little more detail later, but suffice to say that it is nowadays easy to integrate many of the necessary logistics under one heading, so this should not be a primary concern.