Being an Urban Explorer and living in Atlanta I know of many. That said many are 'no tresspassing' but I am happy to provide that information. Some others don't have any signs and I have shot there before.
I also know of a studio that you can rent that might fit the bill. Shoot me a PM or email firstname.lastname@example.org
and I will be happy to provide the information!
Would love to travel along and hang out and see the shoot or give a hand if you need a 2nd shooter, lighting or whatever else.