I heard that Mountain Biking Georgia is the best georgia trail book so when I saw it used on Amazon for 1 cent (and $3 shipping) I grabbed it. It’s pretty good for $3.01.
It doesn’t have any south Georgia trails, probably because it was published in 1998. I guess it should really be called Mountain Biking North Georgia though.
None of the trails are particularly long so I think the trick would be to link together a few of these like the Fools Gold course does. A nice addition would have been a chapter on how to link up a few trails to form an epic.

I hope you can send me an email with more information about the book , if it was any good.
Greetings from Belgium