As a very small volume purchaser - each piece bought for a specific project, I tend to buy hardwoods at the closest and most convenient retail source that has what I want. For me that is almost exclusively Capitol City Lumber or Klingspor's in Raleigh. For you, those are neither convenient nor close.
I make the trip to Atlanta Wood Products (http://www.hardwoodweb.com) in Marbleton, GA (about 2 hours west of Anderson, SC by Interstate). They have a very large assortment of 4/4 and 8/4 lumber in numerous species and a good quantity of each that you can pick through. They also carry many veneers and wood blocks suitable for turning. Be aware that some species are only dimensioned in thickness and may vary in width over the boards lengths. They can cut boards down (many are in 10-14ft lengths) and I believe they offer S4S service for a fee (a little fuzzy there as I dimension and thickness my own lumber as needed). All wood is typically kiln dried. Prices are by the board foot and published on a booklet you can pick up at the front counter, so you know the pricing of everything beforehand, as well as whether they carry such. I would imagine the turning blocks are likely marked for price individually, but I have not bought any so I am uncertain since I do not have a lathe. Just about anything you want is there unless you need something especially exotic.
You can also pick up limited quantities from a limited selection at Woodcraft in Greenville, just off Woodruff Road very close to where you get off of I-85. However, you will typically pay retail prices unless they have a good sale going, but Paul and Brenda are both wonderful to deal with.
If you go our articles section then look on the right hand side for the menu, you can find a regional listing of local sawyers. This might be useful in addition to the great advice Ethan, our SC local, have already given you.
West Penn Hardwoods in Conover, NC. This place is simply incredible. I can't imagine many lumber places in the US being any better. They literally have everything. It seems that pricing is around the national average. I also found a local sawyer in Iron Station, NC that I bought from for the first time recently.