Toy Wiz, eBay and Poke Order are just a few of the many places where you can purchase Pokemon EX cards. These sites provide information on the cards' quality, so you can tell if they are suitable for framing in your home.
If you want to make the image on the cards larger to frame them, it's best to scan the image and have it printed at a local printer. You could also provide the printer with the card to scan it as a high-quality image. With this image, the business is then able to print a large-scale version of the card, so you can display it.