Interested in writing about slavery in the U.S.? This chronology of U.S. statutes concerning the topic is a useful research tool from the Yale Law School.
As you know from your work on Douglass, reading and writing were central to his life as a free man. Why not take a visit to the National Institute for Literacy's site to see what you can learn there?
Here's a site where you can hear the actor Norman Matlock read a speech written by Douglass entitled “An Appeal to the British People.” Douglass first delivered this anti-slavery speech in 1846.
Take a look at this photo of Douglass from Matthew Brady's studio, which now is a part of the collection at the Library of Congress. What can you tell about Douglass from studying the photo itself, its date, its creator, and its present owner?