Kayak Diving provides an extremely comprehensive article on this new and exciting mode of onshore diving. The site also provides info on the availability of the kayak divers' bible: "Kayak Diving - The Complete Guide...", a book designed to be used as a manual for the specialty classes, and reviews of various dive kayak models.
SportDiverHQ is a complete resource of information for serious sport divers. Information on training, nitrox, mixed gases, wreck and cave diving as well as interesting articles and useful charts and tables are provided.