First of all, go back to your My eBay page and click on the Account tab. Look at the right hand side of the screen of the page that appears on the screen - there is a heading there which says "Account Preferences." Click on the second option from the top of the list beneath that heading - this is the one that says "Site Preferences."
When the next page appears on the screen scroll down the page until you see the sub-heading that reads "Postage And Packing Preferences." Click on the Postage Preferences link and a new page entitled "Manage Postal Settings" will appear on the screen. Scroll right down to the bottom of the page and you'll see an option that says "Exclude Postal Locations." Click on the Edit link to the right of that line. This will bring up a new page like the one already shown in one of the earlier responses on this thread.
When the next page loads up scroll down to the bottom half of the page, which is entitled "International." Tick the main box next to every overseas region shown in that section. By doing that you will automatically be blocking every single country that falls under that region. Once you have finished doing this scroll further down the page and look for the option that says "Also Apply To Current Listings." There is a box next to that sentence - tick that box and this will ensure that the updates are applied to your existing listings and not just the ones you create after having blocked those countries.
Finally, once you have done all of the above scroll right down to the bottom of the page and click on the blue "Save" button to confirm the changes. Once you have done this it will not be possible for any buyers with a primary address in any countries outside of the British Isles from being able to purchase anything that you list for sale on the site.
