I don't know if you have a chainsaw or if you only want dry.
If you have a chainsaw keep an eye on Craigslist under the "free stuff" category. I just checked Greensboro and there are 18 listings for "fire wood".
Also check with tree removal companies, trimmers for power lines, even firewood suppliers. If you check Craigslist under All you get the firewood sellers as well (total 57 listings); homeowners usually use the Free Stuff category.