limiting sales to the USA

Is there a way to limit the sale of digital items to customers from the USA only?  I want to avoid the tax issues with selling to other countries for the time being.  I saw that there is a way to set up shipping zones, but will that work with digital products?

How do I limit the sale of physical goods to only the United States? 

5 hours ago, Rtampa333 said:

How do I limit the sale of physical goods to only the United States? 

when setting up your shipping option you have to add shipping zones. you simply only add the United States and omit any other country.