Ed Buckner (former president of the American Atheists) is placing them in Red Top Mountain State Park and A.H. Stephens State Park. Other books to be donated include Faith Fear Fact Fantasy by the late Dr. John Henderson and Why I am not a Muslim by Ibn Warraq. (These two titles were donated by the American Atheists.)
You can check out The Friendly Atheist's article here.
1:05 pm update: Tyler Morning Telegraph - Atheist texts delivered to Georgia state park