by Jim » Wed Dec 30, 2009 11:04 am
You can select which countries you will accept orders from on the Commerce Setup > States and Countries screen. If the country is not enabled the shopper won't be able to select it and can't place the order.
If you mean you don't even want them to be able to see your site then that would have to be done on the server and you should contact your host to block that country.