Upper Ohio Valley Genealogical Association, Pennsylvania

I am doing research on the Crothers/Carothers/Carruthers family, and I found mention of them in a couple of the volumes of an index that had been listed in volumes 68 and 69 of The Record, which was from 1937 and 1938.
This index covered wills, administrations, marriage records and Orphan Court proceedings for Western Pennsylvania, Northern West Virginia, and Eastern Ohio. In the information, it says to contact the Upper Ohio Valley Genealogical Association. However, there doesn't seem to BE an Upper Ohio Valley Genealogical Association.

Now, I can just contact all the possible genealogical societies to see who might have those records. Or I can ask those who might be more knowledgeable than I am, and cut to the chase. Anyone have any suggestions other than to contact all current genealogical societies that covers these areas?

Thanks,

Margie Geiser