Good to the Food Allergy and Anaphylaxis Network on-line. They have a wealth of information. My son has severe food allergies.
Also, if you want to go to certain Chain restaurants, check out their websites prior to your visit. I know that McDonalds, Wendys, Burger King, etc, all have allergy information on their websites. Also, Chili's is one of the best restaurants I've come across for information. I asked them about their ingredients and they brought out laminated menu cards with safe suggestions for each of the major food allergy groups (milk, wheat, eggs, peanut, etc).