In my area of northern California, I find Sprouts supermarket to be reasonable. One of our big costs is bread... my wife loves bread and has not been able to give it up even though I try to cook other whole foods. They often have Udi's bread on sale and I buy a whole bunch and freeze it.
I agree with other people who have posted here. There are lots of foods that are naturally gluten free, so switch to those kinds of foods. If you stick to things that are traditionally made from wheat it get's difficult to keep food costs low.
For instance, buy corn tortillas which are gluten free from several low cost brands rather than a tortilla made from a mix of other gluten free flours and made to "look" like other wheat tortillas or wraps.
I have a question to anyone out there that may be able to answer it. How does anyone afford to shop glutin free is there a good place to shop that is affordable. I have a house of 5 and my pockets aren't deep enough to afford the cost of glutin free foods. Help