Books
Adams, John. The Adams Papers: The Legal Papers of John Adams. (Harvard, 1965)
Emmons, William, ed. Transcript of the Trial of the Soldiers (1824).
Hansen, Harry. The Boston Massacre: An Episode of Dissent and Violence. (Hastings House, 1970). [This book contains numerous factual inaccuracies.]
Kidder, Frederic. History of the Boston Massacre. (Munsell, 1870).
Zobel, Hiller B. The Boston Massacre (Norton, 1970). [Zobels' book is considered the definitive treatment of the massacre and trial.]
Internet
Boston Massacre (iBoston)
This site includes information on Massacre-related sites around Boston.
Boston Massacre (Historywiz)
This site contains information on the Paul Revere engraving depicting the massacre.
Boston Massacre Historical Society
Library of Congress: John Adams and the Boston Massacre Trial
Video
Discovery Channel. Unsolved History: The Boston Massacre (2003).