www.csaceliacs.org (celiac sprue association) is great for overall information. Lots of times just googling a product you are wondering about as in "gluten free green chiles" for example can provide answers. Some companies provide information on their websites. Many Newman's Own products are gluten free. (Gluten being from wheat, rye, barley & possibly oats). It is true that there are many sources of hidden gluten, and it's wise to familiarize yourself with them. Just googling "gluten free" will bring up lots of options. www.glutenfreemommy has some good recipes, and www.glutenfreegoddess is also loaded with information and recipe suggestions.
Also www.celiac.com provides a list of safe and unsafe foods and ingredients. There are oodles of products these days labeled gluten free, but the best thing to do first, is eliminate the major sources of gluten and stick to whole, natural foods for awhile and see how you feel before launching into the packaged food realm, and introducing lots of flours and ingredients (like tapioca, sorghum, guava bean, etc.) that might not agree with you at first. I still find tapioca flour to be problematic for me.
I don't know where you're at, but Ohio State University and it's Integrated Medicine Dept. is where I've been getting help, and I can't speak highly enough about them. Their director provides lectures and classes in order for people to gather enough information to make this work for them, and then does the blood tests to track the changes. There is also guidance for supplements to address the malabsorption issues if it turns out you do have celiac. I'm not 100% better, but as I said before, just managing better and more often is huge.
My 30 yr old daughter was also tested and found to have the celiac genes, antibodies and physical signs. She's been gluten free about a year. I only wish someone had caught the signs and symptoms with me 20+ years ago. Perhaps I wouldn't have the autoimmune problems, dental, muscle and bone issues I currently feel held hostage by.
I'm thinking you mentioned you have AS & it seems the jury is still out on the no starch diet for that- some people finding improvement, others not. But it is very similar to the diet my rheumy gave me (the really limited one)and I've decided to give that a whirl for at least 3-4 wks if I can, to see how I feel on that as well. Starting tomorrow....
Cheers and good luck to both of us!!!