I know that you can order Bob's Red Mill flours in 25 lb bags online or by mail order. I don't really like many of their pre-made mixes, but I love buying their flours. I'm fortunate to live near their store, so I always go there to buy in bulk. Their mixed gluten-free flour is $34 for 25 lbs, white rice flour is $17.80 for 25 lbs and tapioca flour is $29.25 for 25 lbs. This is how I buy the flours that I use most often. I do a lot of baking and it really saves money to buy in bulk in the long run. I think it's a waste of money to buy things that I can easily make like cookies, cakes, and brownies. I may just change my mind when I start graduate school though.