The best Bishop information I've found is at:http://members.aol.com/jblue46498/bishop.htm
I think you'll find your John's there. I'm stuck on my gggrandfather's parents James W. and Ann (?) Bishop. Their son, Joseph A. Bishop, was born in 1836 and I don't know if he had siblings or his mother's maiden name to go back further than that. Happy Hunting!