Go do some research at your local library and your local DAR association...
The library may have maps archived that would show private cemetaries, or what were once cemetaries, in the area (or be able to direct you to someone that would have such).
The DAR will be able to tell you fairly quickly if the names are local names and who their descendants would be (which you might need to know if you were going to exhume the bodies--for permission. They might also be able to shed light on facts.)
And you said someone told you where the gravestones were? Check with that location too, to see if the stones are really there.
Check with the recorder of deeds to see if the property description once included notations for the cemetary.
It is probably a very old family cemetary from the sound of things. You may never know the whole truth... Being from TN, are you familiar with the legend of Daniel Boone? Two states claim his grave--TN and MO. Seems that someone thought he was buried on a MO farm, TN came and exhumed a body, took it back to TN, and the two states have been arguing ever since over who really has the body!! (MO thinks that TN got someone else by accident, BTW.)

So you never know with the old family plots.