A 2005 meta-study reviewed the efficacy of light box therapy for depression. It found bright light therapy was more efficient than anti-depressants medication.
Giant health-related websites are excellent resources, but don't discount the personal mental health blogs on this list. They are the best in the world.
Journaling is an excellent (and free) way to practice self-care. To get you started, here are 99 thought-provoking journal prompts for depression and anxiety.