The Sproat's & O'Neills of Indiana

I have been searching for a tie with my Great,great grandfather, James G. Sproat. He resided most of his life in Barnesville, Ohio. His son, James Mason Sproat married Rachel Ellen Seabrooks of Maryland. Mason and Rachel grew up during the Civil War, so I am assuming that his Father was born about 1830's. I need some information about him. I know he died when my Grandfather (James C. Sproat) was a small (6-10?) year old boy from his stories. Where in Ohio, assume Barnesville, or nearby because of his Wife Matilda and children who stayed in the area.
I am also searching for Thomas O'Neill of Rathfarnham, Ireland. He was my Great grandfather on my Mother's side of the family. He immigrated here in 1882 per the records we can find. We know he married Mary Hannon in Dixon, Illinois. He had several childred: William, James, Henery, Charles, Agnes, Mick (Marian),to name a few. they all left the Chicago area and settled in Indiana. I cannot find his link in Ireland. Any help would be appreciated. I can only find a babtismal record in 1862 (his date of birth) in Rathfarnham that fits.