My daughter was also allergic to milk, eggs, soy, peanuts and pineapple. She outgrew her milk allergy at 3, but has since added fish. As for egg, do not use egg substitutes in the supermarket and tofu is not an option for you since I believe it contains soy. Someone already gave you several good options for egg substitutes earlier. They all work very well.
It does get easier. I have found FAAN at www.foodallergy.org to be a wonderful resource. The sell a cookbook: The Food Allegy News Cookbook that has a lot of good recipes...mostly baking ideas. There's also a brand called CherryBrook Farms found at Whole Foods and some at Kroger, that offers mixes for cakes and cookies. I've found the cookies to be good...the cakes were okay. As for birthday cake, here's an easy recipe if you want:
INgredients: 1 1/2 cups all-purpose flour, 1/2 teaspoon salt, 1 cup white sugar, 1/4 cup unsweetened cocoa powder, 1 tsp baking soda, 5 tablespoons vegetable oil, 1 tablespoon white vinegar, 1 teaspoon vanilla extract, 1 cup cold water, 1/2 cup semi-sweet chocolate chips (I found vegan ones at whole foods or the walmart brand semi-sweet are also milk free)
Directions: preheat oven to 350 degrees.
Greese 8x8 pan or use muffin pan with liners. I like this recipe because it holds together for cupcakes, whereas most other egg free recipes do not.
In large bowl, combine flour, salt, sugar, cocoa powder and baking soda. Mix well with FORK. then stir in oil, vinegar, and vanilla extract.
When dry ingredients are thoroughly moistened (I usually add about 1/2 tsp more of oil), pour in cold water and stir until batter is smooth.
Stir in chocolate chips and pour batter in prepared pan or muffin cups.
Bake for 30 - 35 minutes for cake, until toothpick inserted in center comes out clean. Cool on rack.
For cupcakes, I bake for 23-25 minutes. I remove from pan immediately and cool on rack. If you leave them in the pan, they tend to get oily on the bottom.
As for icing, I use Duncan Hines Creamy Homestyle Classic chocolate as it doesn't contain any milk, eggs, soy or nuts.
Another option is to check out www.divvies.com
Good luck!
J.