NewspaperAbstracts.com a site devoted to publishing online extracts from US newspapers prior to 1923 submitted by researchers
Newspaper Obituaries On The Web - Mississippi a directory of over 6 million newspaper obituaries
NewsDirectory.com - Newspapers: Mississippi search millions of articles in thousands of newspapers by topic or keyword
Obituaries - Mississippi database of archived newspaper obits, by US GenWeb
United States Obituary Collection - Mississippi a database of thousands of obituaries in dozens of this state's newspapers
Vicksburg National Cemetery  largest number of Civil War interments of any national cemetery in the United States

Additional Resources at Ancestry.com

Mississippi Census, 1805-90
Mississippi Marriages to 1825 over 8,500 names
Mississippi Marriages, 1826-1900 over 22,000 names
Mississippi State Database over 250 databases for Mississippi here, including military rosters, censuses, marriage and birth records