Voss is in Germany and in the USA a very common name. It is German dialect and means fox - because of the red hair or the intelligence of the ancestor who got the name first.
To find your ancestor, you should know, where you great-grand-father came from. If you did find out the birth-place, you can try in this town. In Germany state registries exist since about 1870. Before you must know the church where your ancestor is registrated 8baptism, marriage).