Yes: Both Forbidden planet and a small store in the Oasis market sell Yu-Gi-Oh cards. The Oasis store buys too I believe.
hobby shops collector stores
In the UK many stores sell Yu-Gi-Oh cards. Check out any of these stores: 1. Argos 2. Tesco 3. Hobby Shops 4. GAME There could be more shops in UK that sell them but they're the best stores to go to.
Twilight edition will be sold in local hobby stores, as well as large retailers such as target, walmart, and eventually Kmart.
Ebay, Amazon, and Yu-Gi-Oh stores
You gi oh sleeves are he little protectors they have. You can find them at walmart or other stores like that.
You can buy Yu-Gi-Oh cards at stores such as Target and Wal-Mart. They are usually found near the checkout isles of the stores. Some stores only have small amounts of Yu-Gi-Oh cards, and depending on what type you want (such as GX), you might have to look at different stores to find what you are looking for. Hope this helps!