Did you all see this? Amazon.com is now selling groceries. (and if you subscribe to Amazon Prime, you get free shipping.) They have a huge selection of natural foods and a large selection of gluten-free foods. You have to buy in bulk (for instance, you buy a box containing 4 bags of gluten-free pancake mix, you can't buy the bags individually) kind of like Costco.
However, in the Natural Foods section there are lots of gluten-free foods (like Larabars, etc) that aren't listed in the gluten-free section for some reason. I'm excited about this, since I don't have a car so my ability to buy groceries is somewhat limited.