Looking for Gilbert Lee Powell

I have been working on my family tree for months now and while my grandmother on my dads side is coming along nicely, I have come to a dead stop on my grandfather. I can find nothing on his parents. All I know is their names but no birthdays, death dates, siblings, nothing. If anybody knows anything about Gilbert Lee Powell please help me out here. His wife's name is Florence Josephine Koller Powell, his son's name is Thurman Newell Powell and Thurman's wife's name is Omogene Frances Powers Powell. Also Thurman has a sister, Catherine Powell Bremerman. That is all I know. Please help!