Quincy Ruffin's "Mississippi Tears" can be found through the viaLibri website. ViaLibri is a rare book dealer that connects itself to multiple rare book sites; when a search is made, many sites are involved. This allows the user to have access to many reputable book sellers at once.
A search on viaLibri shows that "Mississippi Tears" is available from ABAA, Biblio, AbeBooks and Alibris. The listing on viaLibri has the seller as Bolerium Books for all of these websites; this indicates that the book has been listed multiple times by a single seller, but it can be obtained through any of these sites.