* Online retailers: There are many online retailers that sell Yu-Gi-Oh cards, including the official Konami website. You can often find good deals on cards online, especially if you're willing to buy in bulk.
* Card shows and conventions: Card shows and conventions are a great place to find Yu-Gi-Oh cards, especially if you're looking for rare or collectible cards. You can also meet other Yu-Gi-Oh players and trade cards with them.
* Garage sales and flea markets: Garage sales and flea markets can be a great place to find Yu-Gi-Oh cards, especially if you're looking for older or rare cards. You can often find cards at a fraction of their retail price.