Here's where I went: http://www.suwaneelumber.com/
Based on google maps, that's about 3 hours from you.
I was happy with them. The prices seemed pretty good, and you could buy in any quantity. Even just one board (which I ended up needing to do, since my initial calculations were just a bit off).
But I agree ttownshaw, it sounds crazy they there wouldn't be more availability in the woodworking capital of the country.