Africans in America: The Revolutionary War (PBS) (a good place for pictures)
Wikipedia's African American in the Revolutionary War
African Americans in the War for Independence
African Americans in the Revolutionary Period
Biography: James Armistead Lafayette
American National Biography: Peter Salem
US Gen Net Archives of Military Records (hint: "Control F" to find your person's name)
National Liberty Memorial ("proposed national memorial to honor the more than 5,000 enslaved and free persons of African descent who served as soldiers or sailors or provided civilian assistance during the American Revolutionary War.)
A Primary Source Document is a physical object that existed during the time period being studied and can give you an insider's view of events. These may be letters, diaries, bills of sale, works of art, war documents, or any official records.
British Pass Issued to Black Loyalist, 1783
Bill of Sale for Drumheads, Prince Hall to Boston Regiment, 1777
Portrait of a Black Revolutionary War sailor, 1780
Boston King's memories of the evacuation from New York, 1798