First of all, go back to your My eBay page and click on the Account tab. When the next page loads up look at the right hand side of the page where it says "Account Preferences." Beneath that heading are a number of options - click on the second one from the top and a new page entitled "Site Preferences" will appear on the screen. Scroll down the page until you get to the section entitled "Postage And Packing Preferences, then click on the link that says "Postage Preferences."
Once you have clicked on the link a new page will load up which reads "Manage Postal Settings" at the top of the page. Scroll right down to the bottom of the page. In the bottom left hand corner you will see a sentence that says "Exclude Postage Locations." In the middle of that line are two options, the first of which is "Domestic", whereas the second is "International." To the right of that line is a link that says "Edit", which you will need to click on in order to get to the section you need to locate in order to make the necessary updates.
Once you have clicked on the "Edit" link a new page will load up. The top half of the page is for domestic destinations, whereas the bottom half of the page is for international destinations. Go to the section entitled "Domestic" and look for the box next to where it says "Northern Ireland." Tick that box, then once you've done that scroll further down the page until you see the box next to the option that says "Also Apply To Current Listings", then tick that box. If you do that the blocks will be applied the moment you click on the blue "Save" button right at the bottom of the page in order to confirm the changes, in which case from that point onwards nobody with a postal address in Northern Ireland will be able to purchase anything from you.
