Step I review -- This is also by KU Medical School, very helpful site.

Pathology Review -- Great site, contain online-tests, questions and explantations.

USMLE offical site -- need i say more?

National Board of Medical Examiners -- Information about licensing exams, research publications, and grant information.

Federation of State Medical Boards -- The Federation of State Medical Boards of the United States, Inc., is a national organization comprised of the 68 medical boards of the United States, the District of Columbia, Puerto Rico, Guam and the U.S. Virgin Islands. On behalf of its membership, the Federation's mission is to be a leader in improving the quality, safety and integrity of health care in the United States by promoting high standards for physician licensure and practice.