There are two in the Jackson area every year. Cinderslam in the spring and Red September in the fall.
Hattiesburg hosts two a year so far. Union Strike in late summer right before school starts back and Hattiesbrawl in November.
Look up the Mississippi Fighting Game Union on facebook. http://www.facebook.com/groups/mfgu.fgc/
There has been some talk about more from some other folks but no news as of yet about them.
Also New Orleans and Shreveport Louisiana have events very often.
Louisiana Fighting Game Community http://www.facebook.com/groups/LouisianaFGC/
New Orleans Fighting Game Community http://www.facebook.com/groups/FightNightDIbbz/
Arkansas hosts several evens year. The biggest being a major called ARK that has been around for five years and brought some heavy hitters this year like Justin Wong and Ricky Ortiz.
Arkansas Fighting Game Network http://www.facebook.com/groups/373796221942/
Gulf Coast Encounters hosts some pretty regular events.
Here is their facebook page http://www.facebook.com/groups/279241248830211/
ABXY Fight League, an Alabama group http://www.facebook.com/groups/150638181624530/
Also the Alabama Fighting Game Club http://www.facebook.com/groups/304232252933470/