AmyDel is GF, but she's also rather busy so isn't around too often. Moonglow is another good source of information, but I haven't seen her around in a while. Maybe gophergirl is around. I know a bit about special diets, but not allergy- or Celiac-specific diets. Given that he hasn't actually started a strict GF diet, I'd probably worry less about things like spices that might be cross-contaminated with gluten and focus more on not feeding him a steady diet of bread and pasta. That said, GF products are becoming fairly mainstream so you can likely find GF bread and pasta at most grocery stores (though I have no idea what brands are good). As a general rule for special diets, I find it helpful to think about what the person can
eat. There's all kinds of stuff that doesn't contain gluten: fruits, vegetables, meat, beans, dairy. Of course there's the possibility of cross-contamination with just about anything, but if you're focusing on the confirmed presence of gluten then read labels. There are a lot of mainstream foods (like most Chex cereals) that are GF. As far as cuisines, I'd tend toward things like Mexican or Chinese, where it's easier to find stuff that is corn- or rice-based and doesn't need to do anything special to be GF. People who actually know what they're talking about might be able to chime in with helpful information, but in the meantime Google can be a good resource: "GF kids" or "GF fast food," etc.
BTW, I will eventually get around to replying to your PM.