Ballew Kinnaman's Allergies Site -- Pointers to net-wide articles about various allergies. Searchable archives. Home of several mailing lists, rubber/latex, thyroid, computer health, and the allergy list
Latex: When protection is a danger -- Naples Daily News (Florida) article
Guide to Plant Relationships (for food allergy and intolerance identification) -- Excellent and detailed site
Dr. Duke's Phytochemical and Ethnobotanical Databases -- Information about the chemical makeup of foods
Hypoallergenic Cosmetics -- FDA official information about the term "hypoallergenic." Basically, the term is meaningless and has no legal definition.
Yahoo - Health: Diseases and Conditions: Allergies
Yahoo - Health: Food Allergies