One of the most famous black women was undoubtedly Rosa Parks (February 4, 1913 - October 24, 2005. She was the made famous, because she refused to give up her seat to a white person. She was arrested and she spurred the bus boycott movement in Montgomery Alabama. She fought segregation, and won. The supreme court ruled that the segregation practices in Alabama were unconstitutional.
A more recent woman that deserves mention is Condoleezza Rice. She was born in November 14, 1954, and was served as the 66th Secretary of State. She was the second woman to hold this position. This shows how far black women have come in America.
These two women should get you started.