Find the property owner... Try the county tax assessor office. many counties have a website with a map you click on a plot and it gives you the owners name and address. Some are better than others. Then, if there's occupied property nearby you can ask the residents if they know the owner. It well may be them or somebody in the family. Often a grandparent left the property divided among their children, who built homes on there land. The children may still live there.