1.) Sulking in some sympathetic goat herd's shack in Pakistan. He probably has only minimal contact with supporters and then only though one or two trusted intermediaries that are not obvious terrorist sympathizers. He never uses electronic communications. If this is the case we probably have little idea where he is and can only hope that he will break cover.
2.) Protected in a country with which we do not wish to have a public confrontation at this time. Maybe Iran. Perhaps North Korea. More ominously it could be Russia or China. He may be little more than a prisoner at this point and is being kept in cold storage until they can determine how best to use him against us. If this is the case we probably know exactly where he is.
My money is on something close to option #1: He loves attention and his ego will eventually drive him out into the open where we will kill him. I think we should be doing more to encourage him: Call him a coward. Say that we have defeated him and he is hiding like a sissy while others die in Iraq and Afghanistan. If he is at liberty we can get his dander up.