JSTOR is a good option for researching historical topics. You'll find JSTOR on the library's databases page. You'll find a link to the databases page below.
Searching JSTOR can be tricky. Ask a librarian if you're not having success.
Below you'll find some articles that can be found in JSTOR. You can of course find more by searching. Try doing an advanced search and limiting the subjects to African American Studies and History.