It isn't easy. You're right - if you read labels (and I can tell you probably have been), many things have what I'd call "hidden wheat" in them. Modified food starch, for example, is a wheat derivative.
From my experience, the best place to find wheat-free products is in health food stores. I know it's a bummer to have to go to a special place to shop, but this is the best way I know to find your largest and best selection of wheat-free products. However, be sure to read the labels there, too. There are a few products that they sell which contain wheat also. Ask someone who works there what the best wheat free products are.