Hello Alice!
Unfortunately, the only thing that I could find in respect to
the Cumberland County Genealogical Society is the following PO Box.

Cumberland County Genealogical Society
P.O. Box 53299
Fayetteville, NC 28305-3299

Another suggestion is contacting the county Library. Perhaps the
Genealogical Society's meetings are held there or the Library may
have additional information to better help you.
http://www.cumberland.lib.nc.us/lshistory/LSHistory.htm

Just an observation. I am research my paternal surnames MCLEAN, MCKOY/MCKAY, MCDOUGALD and TURNER in the Harnett county area. Also related
names: PARKER, MERGUSON, FERGUSON, BAILEY, COVINGTON, MCNEILL, SMITH, PATTERSON in the Harnett county and surrounding area.

Good luck on your research!
Allen McClain