Srimad Bhagavatam - The text of the Bhagavata Purana and its account of Krishna, in Sanskrit transliteration, with translation and explanation. - http://srimadbhagavatam.com/
Search for the Historical Krishna - N. T. Rajaram argues that Krishna can be identified and placed in history at 3002 B.C. - http://veda.harekrsna.cz/encyclopedia/historical-krsna.htm
Giriraj Mandal - Information about Krishna, Govardhana Hill, and on several temples of Krishna. Includes a photo gallery and maps of Vrindavan and Brij. - http://www.girirajji.com/
Krishna as Kali - Describes how Krishna is worshipped as Kali and the scriptural background for the worship. Presents the Yantra and Mantra for worship. - http://www.shivashakti.com/krishna.htm
Krishna - An account of Krishna in the light of some texts and teaching from Buddhism and other religions. - http://www.nijanand.org/krishna.html
Lord Krishna - Includes an account of his life, links to illustrations, art and other articles. - http://krishna.avatara.org/