The National Park Service Visitor Center, located at 50 Moraga Avenue at the Presidio, provides information on the Buffalo Soldiers through topical books on sale in the bookstore. There's also FREE stuff including the brochure feature on this page. The brochure is all about Buffalo Soldiers and the Presidio. Very cool.
And, don't forget to check out the wall-sized enlargement of the Buffalo Soldiers flanking President Theodore Roosevelt at the Presidio Golf Course during his 1903 visit.