I'm in NC but I'm about 3hrs from Wingate. I don't think I've heard of Poulin grain, what we do have here and in the area you're moving to is Tractor Supply. They do have a website and it has a store locator, I think your location will show up as Monroe but is probably within 10-15 miles of Wingate. I buy there(Tractor Supply) and they carry Purina, Nutrena and Dumor feeds as well as what I think is a generic type brand, All Stock. I like the Dumor feeds, I think the qaulity is on par with the Purina and Nutrena feeds but the price is better. They also carry a range of Stanlee hay products, alfalfa cubes, timothy, oat, combinations of hays in cubes and pellets, also beet pulp in pellets or flaked and the usual assortment of supplements rice bran, wheat bran, dewormers and goat feed.
You can probably find whatever you need there at least until you get to know the area. Most of them also have a bulliten board where individuals can list things like farrier service or hay from the farm. And of course a lot of the employees are horse owners themselves and can give you reccomendations for farriers, vets, etc. Craigslist is good for finding hay at a better price than the feed stores, you'd probably want to check out the area around Charlotte, Monroe or even Rockhill, Sc.
I am located right off I-95 if you take that route south so if I can help you with anything let me know:) when are you making your move? You do know that summer here is usually HOT and humid? Airconditioning is a must have in cars and homes and fans in the barn if your horse is stalled, fly masks and flyspray are pretty much in use from March/April through October. If you want to pm me with a mailing address I can send you any of the horse mags, the freebies they put out in some of the local feed stores, usually a lot of advertising for equine services in the Carolinas.I'm pretty sure that whatever discipline you follow you'll be able to find barns, shows, ect eithin a reasonable distance in that location.
Let me know if I can help from here. Good luck :)