There are a few of us not in NOLA but within an hour drive. There are a few boarding places in the city itself but most people live/keep their horses outside the city. As for riding in the city - it is pretty much riding in the city park or on the levees.
There is quite a mixture of english and western around here, just depends on what barn you go to. I think it is mostly english in the city itself. I pay about $5/square bale but it is just a grass mix hay, the good bermuda or straight bahia will cost a few dollars more.
As for hurricanes, again it really depends on where you are. I live an hour north of NOLA and while I had quite a bit of water with Katrina and much wind damage, I felt safe not evacuating my horses. I am pretty sure all the horses in the barns in the city were evacuated for Katrina.
I've got to run to an appointment but I will try to think of some more tips for you and check the post later.
Can I ask why you are considering moving to NOLA? Just curious, you can tell me to mind my own business.