Don't give up. I feel that way a lot because I have a common family name live in an area where everyone used that name related to the same name on both sides of the family. Probably related on the same side. Everytime I say I am giving up I find something else that just keeps me going. I work my mom's family for a while and when I hit a brick wall there I go to my dad's family.
I don't know if I can help you much, but I use to leave across the alley from some Kirksey's, in fact a great nephew and his mom and sister live across from my dad now and the grandfather is the security guard at the Virgina State Library. If you can get me some info on your Kirksey's I will check with Mr. Kirksey for you. He's well in his 70's closer to 80, so he can probably help. The two brothers I know are Ulyseses and Alphnoso. Ulyseses died some years back, but the other is looking good, everytime I go to the Library he's asking about my family. I remember as a child their mother who was very old came here from Texas and they had some neices in New York or New Jersey. The younger Ulyseses is the conductor of the Petersburg Symphony Orchestra, so you may be able to find something out through that information. Any help I can give I will be happy to help you.