Arthurian A2Z Knowledge Bank: An online glossary of Arthurian characters, places and facts.
Sources for the Study of the Arthurian Legends: Alan Lupack's bibliography of Arthurian sources.
Arthuriana: The website for the journal of Arthurian studies.Malory's Morte Darthur: From the Legends site, has info on the text and links to Caxton, and critical essays.