A Columbine Site

Notes: The most comprehensive database of everything to do with the shooting, the boys, and the victims. It seems like it is still updated pretty regularly as well.

Columbine Massacre Forum

Notes: A forum for discussing anything related to Columbine that allows space for respectful debates. There is a lot of information here that you won't find anywhere else.

Birth Fact Death Calendar

Notes: This website has information on all sorts of murderers, victims, and other assorted criminals. Whoever runs it or works on it does more thorough research than most, managing to find records of some very obscure people.

Murderpedia

Notes: Anyone who has ever killed someone or many people can be found here. I have loved visiting this website since I was 13 years old.