Medline Plus is Service of the US National Library of Medicine and the National Institute of Health:
http://www.nlm.nih.gov/medlineplus/varicoseveins.html

The Federal Government Source for Women's Health Information:
http://www.4woman.gov/faq/varicose.htm

The American College of Phlebology is the premiere association for physicians and allied health professionals working in the field of phlebology:
http://www.phlebology.org/