First I will urge you to try packing your own food if possible. Every time I go on a trip I pack a cooler and have a bag of non-perishable food. This is to give yourself time to heal. I do eat out but every time you do so you take a large chance of cross contamination.
One of the good things about the fast food places these days is that if you go to their web site, most will have wither a list of their gluten-free items, or a list of all ingredients for each item, or a chart showing which foods have any of the top 8 allergens. This is true for McDonald's, Hardees, Burger King, Wendy's and others. So think of a place you might stop and then go to their web site and look. Some places you can forget about eating at include Taco Bell, Pizza Hut and KFC.
Outback, Bonefish Grill, and Carraba's have gluten-free menus you get get online. Don Pablo's, Chilis, Bob Evans, Chipotle, and a whole slew of other restaurants have lists you an get by calling or e-mailing.
Finally, if you go to the site below, there's a large list of restaurants and what they can (or can't in some cases) offer. Can't say how up-to-date all of them are, but you can always contact certain restaurants for the most recent list.
http://health.groups...illyYaks/files/richard