Here is a recipe I have begun using for Gluten Free Baking Flour:
2 c Brown Rice Flour
2/3 c Potato Starch
1/3 c tapioca Flour
1 t Xanthan Gum
Mix all together. Store in an airtight container until use.
Most of the above ingredients are available from multiple companies, and can be found in the Gluten Free section of your grocery store. I like Bob’s Red Mill http://www.bobsredmill.com/ products, which cn be purchased at most groceries, or purchased online.
xanthan gum is an expensive product, and as you can see, it is used in small quantities, so you may want to purchase it from a bulk foods department where you can buy just a little at a time. If you live in the Fort Wayne area, you can purchase it at the Three Rivers Natural Grocery http://www.3riversfood.coop/. It’s on Sherman Avenue a few blocks south of the zoo. If you live out of the Fort Wayne area, try your local health food shop.