Keep in mind that there are many important libraries and research centers in the New York metro area, to which you have access.
Resources for African Studies:
The Research Libraries of New York Public Library are excellent sources of information, including archival primary sources as well as supporting literature.
Catalogs:
NYPL Manuscripts and Archives Catalog
Collections:
Schomburg Center for Research in Black Culture
Manuscripts, Archives and Rare Books Division
Stephen Schwarzman Building (Main Library)
Manuscripts and Archives Division