I would expect the weather to be hot and humid, temps probably in the eighties at least until you reach the higher elevations of North Carolina. Because of the mild winter, I think the bugs/ticks will be bad this year too. I would think the water sources in GA should still be fine in June, but they can get sparse later in the summer with the droughts we have had the last few years. If you are looking for views, you would be a lot better off starting in NC maybe at the NOC/Wesser or Fontana, as there isn't much to see in GA.
I don't have the Databook, but I do have the ATC guides and maps for both GA/NC (Springer to Smokies) and TN/NC Smokies to Damascus and would be glad to let you borrow them if you like. Just PM me your email address and we'll work out the details.