The landman would be whomever contacted you to lease or buy the minerals. If I had to guess, the 1912 lease would be his last one, so researching the title chain is probably pointless unless your family still owns the land. The main issue you will have is determining your grandpa/ma or great grandpa/ma’s heirs and who all gets what. Its basically like building a family tree from 1930 to see who the heirs are and likely why they are calling and what they are interested in. Im not sure on how to search WV counties doccuments, Im sure someone on here can help ya but if they sold it decades ago, you wont find anything that will help you out.