I had bought my original package of Burt's Bees wheatgrass seed at the natural foods store, but in checking the Burt's Bees web site, they have dropped the product.

I still had some left, so I planted that with some "Cat Grass" seed I found at the local home improvement store (a local chain, Chase Pitkin). The seeds look different, but the resulting grass looks and smells the same...
Here are some web links for online merchants:
http://www.sprouthouse.com/http://www.sproutman.com/sproutseeds.htmlhttp://www.gourmetgreens.com/product.html