Whether it be within my circle of friends, while at work, church, and even the grocery store, I seem to be a magnet for people asking me all about milk allergies. Since I've dealt with my daughter being allergic to milk since she was an infant (she is now 6 1/2 yrs old), I am usually able to answer the questions aimed at me. One resource I tend to give is the food allergy and anaphylaxis network:
Milk Allergy Facts, Symptoms - Facts
One thing that I have learned over time is that dairy is not just in food, but also skin care products such as lotion, shampoo, and soap. So, read ingredients on foods as well as anything that contacts the skin.