We have a couple more gluten free restaurants across this fine state.
Buffalo Bump Pizza located at Four Corner's near Bozeman now offers a GF crust and soy cheese for those that can't do dairy. I haven't talked with them about practices to avoid cross contamination but I did sample the pizza at a friend's house the other week and it was really good. They are located at 28901 Norris Rd.
In Missoula The Mustard Seed Asian Cafe now offers a gluten free menu. I have no idea how much it offers or how careful they are with cross contamination but I wanted to share the news. If you have a chance to try them or talk to them please share any information. They are located in the Southgate Mall.
Another Missoula gem is Bernice's Bakery that will do gluten free if you call ahead. I'm not sure what they offer or how much notice you need to give them so again if you have more information please share!