This is a website with a lot of food that will fit in a Feingold diet. It also has quite a few gluten/casein free items, no nuts items, and food to fit other allergies.
You can go to the middle of the page where it says "Search products by allergen" and click on Feingold Stage 1 or Feingold Stage 2 to see the products that she carries. It seems like it only works if you click on stage 1 or stage 2, not both at the same time.
Please realize that these products are mostly "health food" items and the Feingold list has many more name brand products that you can find at any store.