i can't really help you as far as fishing the mississipi river backwaters, but i can definitely give some pointers on bait-
cutbait is fantastic; the fresher it is, the better. i like to catch a pile of 4" bluegills and fillet them out into 1" strips. the most common forage fish is probably the best baitfish to use.
chicken livers work, but they're fragile and don't last long. you get one hookset per liver, then you'll have to put a new one on. that said, chicken livers are incredibly effective and will catch cats if there are any in the area.
waxworms are good, pack as many as you can onto a jigging spoon or large teardrop jig, but be sure to leave the hook point exposed or you'll miss fish.
nightcrawlers will work as well, pinch off about 2" of crawler and thread it on the hook, maybe leaving a tip to squirm and wriggle.
live minnow could work, as long as they're legal to use. i have no experience since it's illegal to use them where i'm from.
you could also try dough baits, stink baits, and other catfish-specific packaged baits.
if you're jigging, you might be able to get some on plastics or bare spoons, but you'd better be in just the right place for it, and the fish would have to be a bit more aggressive.
always make sure there's plenty of hook point showing, and choose your hook according to the size of bait and the size of the fish you hope to catch.
that's pretty much all i've got. be sure to let us know how you do!