The Black Moon Project - Offers news, guides, reviews, forum, and scans of CD covers, magazines, and game manuals. - http://www.classicgaming.com/blackmoon/
Disctronics: CD Interactive - Offers format information including disc standards, video, and audio specifications. - http://www.disctronics.co.uk/cdref/cd-rom/cd-i.htm
About.com - Presents cheat codes and FAQs for over 30 games. - http://vgstrategies.about.com/games/vgstrategies/library/cdi/bl_cdi.htm?terms=cd-i