I'm a big believer in fun, especially when it comes to eating. And just because your child is on a gluten-free diet doesn't mean he or she should be deprived of one of life's greatest pleasures. It will require a little extra work on your part, but its well worth it.
Don't think your choices are limited to carob and fruit-juice tofu, and don't limit yourself to the health food stores (unless that's your preference - I should have mentioned that I'm big on fun, but I'm also big on junk food; I think its an important part of growing up).
Learn to read labels carefully, and to call manufacturers. Even if a label appears to be gluten-free, you should call the manufacturer to make sure there are no hidden ingredients, and to ask about manufacturing procedures. Many chocolate bars, for instance, are coated in flour to keep them from sticking to machinery and wrapping.