American Medical Association
National society's site with many useful areas and more links

California Medical Association
California society's site

Los Angeles County Medical Association
LA County society's site

SCPIE
Professional Liability Insurer based in Southern California

The Doctors Company
Professional Liability Insurer serving most states, based in Northern California

NORCAL Mutual
Professional Liability Insurer based in Northern California

A.M. Best Company
Provides current financial information and ratings for all major insurance companies

Medical Protective
Nationwide insurer owned fully by Berkshire Hathaway