Make sure when you're buying retail, that you buy from the Blaster Boxes (normally 7 packs in a small box for $20), because those are most likely unsearched. Raw packs can be felt through to see if they have wider or metal cards.
www.comc.com is the site I was talking about. Great place with millions of cards for sale, which has announced that it will begin cross-listing almost all cards on eBay as well. However, it will continue to be cheaper normally to buy on the site rather than through eBay or Amazon.