Question - are you from close by? Can you visit Louisiana, or have you been there before? It's sort of hard to capture the culture if you haven't, because of all the Cajun influence.
I don't know much about New Orleans hauntings, but there are haunted tours you can take if you make it down there.
One place I would heartily suggest is Natchez, which is in Mississippi across the river from Louisiana, and has far more surviving antebellum homes than any other place in the country--something like 5000 of them. Longwood is a neat place with a cool story behind it, but it's still unfinished so no one lives there. The coolest ghost story I've heard from there is the King's Tavern story. King's Tavern is one of the oldest buildings there, and sometime in the late 1700's or early 1800's, a bar wench named Madeline went missing. She had been having an affair with the tavern owner, Richard King (I think that's his name). In the 1930's, what is presumably her body was found bricked into the fireplace along with the bodies of two other men and a jewelled dagger.
Natchez has many other haunted claims, but that's the one that stuck out to me. And it's got a lot of huge "townhouses" (which look like plantation houses, but aren't, because it was THE "vacation spot" city during the antebellum area and many rich plantation owners and nouveau riche built houses there). Two other sources rife with supernatural potential are: the Natchez Indians, who were pretty much annihilated in a battle with the French at Fort Rosalie, in the early 1700's (the ones that were left had to move elsewhere. And Natchez Under the Hill, which was a gross, violent, dirty area next to the Mississippi River, which, like the name suggests, had a very low elevation. It had a bunch of bars and gambling places and was a haven for prostitutes, gamblers, thieves, etc. There was something like an average of one murder per night there. Later on, after the decline of Natchez as an economic power, Under the Hill was washed away by the river. Here's a link to some info:
Adams County, Mississippi - Natchez Under-The-Hill
Hope this helps. If not, you know, there are antebellum and postbellum mansions ALL OVER the South, in just about any little town. The places where they aren't antebellum ones are big cities (and take "big city" with a grain of salt, because that includes places like Corinth), because they were burned by the Northern armies. There're a couple of them in Oxford, Mississippi (another cool place for a ghost story, it's got a neat history as well); there are some in Holly Springs, there's at least one in Canton. IMO you'd be better off choosing one that isn't famous like Oak Alley and Myrtles.
If you check the national register of historic places, you can evaluate pretty much all of the registered ones if you so choose. Here's a link to the database:
NRIS Search by location
Not all of them will be registered, though. If you want to look for a historic home within a certain town, you should call that town's visitor's bureau, and they should even know about the privately owned ones.
You might even want to just find a house that you really like the architecture of, and another that you really like the history of, and put them together and make up a name for it.
Good luck!
