MedicineNet - Content-rich commercial site includes interactive groups, ask-the-doctor feature, medical dictionary, comprehensive drug information, medical news, disease-specific information, and links.
Medscape - Searchable commercial collection of full-text articles from such useful sources as the National Institutes of Health and the Centers for Disease Control and Prevention.
Oncolink - Huge collection of cancer information and links based at the University of Pennsylvania. The best starting place found for cancer information.
ParentsPlace.com - Not health-only, but this commercial site contains many pages of sophisticated, reader friendly information on children's health issues.
Medical Matrix - Physician maintained commercial database of annotated health links. Oriented toward medical professionals, but accessible to an educated lay person. A keyword search gets you to a subject index, from which you navigate to the links you want.
American Independent Dentist's Association - dedicated to the survival of the concept of optimal care in dentistry. Working to re-engineer organized dentistry and bring new tools to the education of patients.
American Medical Association - another useful site with links to consumer health information, vast AIDS information center, searchable database of more than 650,000 physicians
Association of Managed Care Dentists - a non-profit organization dedicated to the education of dentists and related professionals about the emerging managed care delivery systems.
National Association of Dental Plans - NADP representative and recognized resource of the dental HMO/PPO industry with news, meetings, statistics and other resources.