One of the southern states I have done research in is North Carolina. My mom's ancestors, surnames - CROWDER and RHODES, lived in Wake County. While researching them I found a couple of websites that I like to use for researching them. They are specifically geared towards North Carolina. They are:
North Carolina State Archives
They have many state government records as well as manuscripts, books, and other items related to North Carolina and the people who lived there. There is no fee to use the site.
North Carolina GenWeb Project
There is access to many records such as census, cemetery, both at the county and state level. There is no fee for this site. You can do a general search for the all of the county sites at one time, or you can go to the specific county and search by county.
These are just two that I like. If you have found a great website for North Carolina let me know and I will post it here as well.