Jefferson & Franklin County Marriages
Ann Geoghegan has just published Jefferson County, Mississippi Marriages, 1805-1900. It is available at http://stores.lulu.com/anniegms. Also available at this site is Franklin County, Mississippi Marriages, 1820-1900. You'll find a couple of other Jefferson County resources at the site as well.
Update: See http://msgenealogy.blogspot.com/2007/09/errata-issued-for-jefferson-county.html for information on an errata for the Jefferson County book.