Spelt flour is a great substitute for wheat flour. You can use it pretty much cup for cup. There is also rice flour but it's a little harder to work with.
My mom has a gluten intolerance and has been eating a gluten-free diet for several years now. She has found that there is a growing-list of gluten-free products in stores now, especially larger grocery stores or natural food stores. When she visits, I tend to make a lot of rice dishes and things like large salads with meat or seafood on top. Also, any mexican dishes that use corn tortillas are good too. She's never been much of a baker, so I don't think she has found good substitutions for wheat flour in baking, but I'm sure there are good recipes out there. I found this link online that might be helpful... Good luck!