I was soooo excited to stumble upon this website! Allergy Eats is a 2012 About.com Reader's Choice site that allows you to search for restaurants across the country that can accommodate your dietary needs. The site is a peer review site, which means the ratings are given by people like you and me. You can select your allergens and location, and the site will generate a list of eateries in your area with allergy friendliness ratings based on 3 criteria: how comfortable was the rater with the establishment's ability to meet your needs, was the restaurant able to accommodate your needs, and how knowledgeable was the staff about food allergies. You can even view restaurant information like maps and directions, nutrition, ingredients, and allergy information (where availible).
The site offers dining tips, links to other allergy friendly sites, and has their own blog to share information. If you're planning a trip to Disney World see their Allergy Eats Disney World section! Registration on the site is free and you receive email updates from them as well. BONUS: this site has an APP!!! SCORE!!!