Electronic Textbook of Dermatology
This material, geared to trained clinical dermatologists, contains chapters on conditions and environmental reactions, anatomy, drug reactions, emergencies and laboratory exams, among others. Last updated in 2000.

Merck Manual, 2nd Home Edition 2004. Section 18: Skin Disorders
This monograph explains disorders, who is likely to get them, their symptoms, how they're diagnosed, how they might be prevented, and how they can be treated; also provides information about prognosis. It is based on the Merck Manual, but written in everyday language by 300 contributors. The Skin Disorders section discusses a spectrum of skin and hair conditions.