So where does the Old Testament state that Satan fell from heaven?

It doesn't in not one place. The only verses that Christians can try to use are talking about the earthly kings, which you so wonderfully pointed out. The NT revelations doesn't count at all because Satan would have had to fall first which he never did. Satan has no power other than what God allows. He never fell, never will. God has nothing to punish him for. He can't take your soul, and he doesn't have little demon buddies who can possess you. What purpose does God have for hell and Satan if Satan is only doing God's will? None. The Christian devil sounds like something out of Paradise Lost. Christians have to believe that Satan fell, or else there's a huge whole in their belief system. Who do they blame evil on now? It certainly can't be an all-loving God..