You can find several African American cemetery listings here:

http://www.dnaco.net/~diva1/cemeteryrecords.html

Also, African American Cemeteries of Choctaw County by Nova Law is for sale here:

http://www.rootsweb.com/~alchocta/books.html

There are also many other Choctaw County cemetery listings on the ALGenWeb site:

http://www.rootsweb.com/~alchocta/cemeteries.html
http://www.rootsweb.com/~alchocta/cemeteriesindex.html

Hope this helps