I think I would find a tree service guy with an off-day and hire him(along with his loader truck) for the day.Get that stuff on your place and you will enjoy the whole proccess a lot more.That is big Hickory.
for THAT kind of a find... I think it might make sense to get a quote from a local freight hauler (18 wheeler) to take it all to your house in 2 loads. Maybe $150 per load? And rent a front end loader to load the truck; $150 per hour. Maybe $600 total and you're done; no one else can horn in on your find and you'll make the mill owner happy cuz it's all gone and he has room again.
If you can get it all for $600 bucks I'd say get it while the gettin is good !
KRS