e-Learners.com is an effective tool to help you identify your options in your search for a specific type of online course/degree. It indexes close to 1,000 online college degrees accredited by the U.S. Department of Education.
Branching off their well-known annual ranking of colleges, U.S. News & World Report offers a guide to online education that contains useful background information on the subject as well as a directory of graduate degree programs.
GetDegrees.com is a good starting point when researching online education options. It combines an extensive database of distance education programs with well-edited articles about career development, and user rankings and reviews of online colleges.