You will find many books on civil rights movements in the E and F ranges on the second floor of the library. The 'E' class covers US history chronologically (by period) and the 'F' class encompasses American history with sub-divisions by region. Big subjects like Civil Rights lend themselves to a wide insterdisciplinary range, however, so your research may take you into other areas as well, including politics, law, sociology, and cultural studies.
Search the CATALOG.
The pdf below includes a detailed breakdown of the Library of Congress' E 7 F Classes: