These folks may have these located.

CHATTAHOOCHEE RIVER LINE BATTLEFIELD PRESERVATION PLAN COBB COUNTY, GEORGIA

http://www.thomasonandassociates.com/River%20Line%20Battlefield%20Plan%20FINAL.pdf

Of interest, see also:

http://www.riverline.org/Documents/RLHA_map.pdf

http://georgiainfo.galileo.usg.edu/topics/historical_markers/county/cobb/johnstons-river-line