Kimberly, I totally feel for your DS. My DD is 14 months old and she was just diagnosed with a peanut allergy. Thankfully we found out through allergy testing instead of a reaction. She too gets eczema a lot. I have not really researched different sites but her allergist said this website was good. www.foodallergy.org
The one Bluebear listed looks good too.
DD's allergist also gave me a list of allergen-free food companies (candy, etc). If you are interested, PM me and I will get that list to you. HTH!