John Posey b. 3/2/1837

My 2nd great grandfather was named John Posey b. 3/2/1837 and d. 1/18/1892 in Warrick co.,Indiana. I have tried for two years to find his parents on, etc. with no luck. Census info has not been helpful because in 1840 it was a slave report and by 1850 he was married and living on his own. I have found no other records that can be definitely tied to his very common name.
I hope that he may fit into the Posey study or that someone has a suggestion for me.
I am female but have a brother. What should be my next step?