Lancelot: Texts, Images, Basic Information
http://www.lib.rochester.edu/camelot/lanmenu.htm
This site offers basic information about Lancelot, as well as an imagery gallery of the character as he has been portrayed through history.
The Camelot Project
http://www.lib.rochester.edu/camelot/cphome.stm
This online database from the University of Rochester has a wealth of information about Arthurian legend and scholarship.
The Princeton Charrette Project
http://www.princeton.edu/~lancelot/ss/index.shtml
This site provides information about the Princeton Charrette Project, and links to papers and other scholarly sources about Le Chevalier de la Charrette. Though the information is especially scholarly and therefore more technical than many might desire, it is an excellent window into the vast and complex world of Arthurian scholarship.
Background Information on Chrétien de Troyes's Le Chevalier de la Charette
http://www.princeton.edu/~lancelot/romance.html
This site, part of the Princeton Charrette Project, provides an excellent background on the manuscript tradition of Le Chevalier de la Charrette.
King Arthur: History and Legend
http://www.britannia.com/history/h12.html
This site is an excellent portal into the historical and mythological world of King Arthur. While many of the other links provide information specifically about Arthurian romance, this site looks more broadly at the Arthurian tradition, especially into its historical nature. There is a link on the page to a comprehensive timeline, which many readers should find quite useful.
King Arthur and the Knights of the Round Table
http://www.kingarthursknights.com/
This site is less scholarly than some of the other links. There is an interesting map of Arthurian Britain, images of Arthurian figures and places, and other pages detailing the history and legend.