I am back to take apart your arguments that he was already dead.
The Taliban first claimed to have killed him (with just as little evidence):http://www.foxnews.com/story/0,2933,41576,00.html
Apart from the obvious point that the news story mentioned that he was supposed to have died of a lung problem, and not by the Taliban, it is also from a member of the Taliban which you seem to have more trust in than the US government.
Pakistani President Musharraf thought he was dead:http://edition.cnn.com/2002/WORLD/asiap
The Pakistani authorities also believed that he was in Afghanistan. Also note that some US Authorities "claimed" that he was on dialysis and others including Rumsfeld rebuked that.
FBI head of counter-terrorism thought he was dead:http://www.cbsnews.com/stories/2002/07/
From the news article. "Watson, speaking at a conference of law enforcement officials at a downtown hotel, quickly emphasized that he had no evidence that bin Laden was dead, but his comments suggest that the FBI has no intelligence that proves bin Laden is alive." I dont need to add any more.
Afghan president thought he was dead;http://edition.cnn.com/2002/WORLD/asiap
From the news article. "The more we don't hear of him, and the more time passes, there is the likelihood that he probably is either dead or seriously wounded somewhere." He WAS heard from again, thus mooting the validity of this article.
French Intelligence thought he was dead:http://usliberals.about.com/b/2006/09/2
From the news article. "The regional newspaper l'Est Republicain on Saturday printed what it described as a copy of a confidential document from the DGSE intelligence service citing an uncorroborated report from Saudi secret services that the leader of the al-Qaida terror network had died." I shall just mention one word "uncorroborated".
Former Pakistani Prime Minister Benazir Bhutto thought he was dead:http://www.youtube.com/watch?v=UnychOXj9Tg
I couldnt be bothered to watch it - although take note of her governmental position - "former" that is.
Former US Intelligence Officer thought he was dead:http://spectator.org/archives/2009/03/1
That is just funny, its almost as if that is a parody newspaper. I will just point out the first sentence "All the evidence suggests Elvis Presley is more alive today than Osama bin Laden." Hilarious.
Many of these are reliant on hear-say, totally unverified evidence if you can even call it that, rumours and obviously people who cant be trusted at all.
Additionally pathetic arguments along the lines of we havent seen him for a few years so he must be dead, tell that to a religious person - "we havent ever seen God therefore (s)he cant exist" and on goes that stupid argument that never gets anywhere near the truth.
An example for you. I used to believe that NASA never landed people on the moon. This was because I had "seen" more evidence to show that no-one had landed on the moon than evidence to show that they had. I was actually put right by people on these very forums, each and every one of my arguments were destroyed - I changed my viewpoint totally, and I admit that I was wrong. I was primarily wrong because the evidence I had seen that claimed that man had not put their boots on the surface of our moon totally ignored evidence to the contrary - I was hooked and ignored any evidence to the contrary.
I am now a sceptic of anything that has not been proven one way or the other, in the case of Bin Laden the primary evidence must come from simple words. The US government say that he is dead, Al Quaeda say he is dead, the Taliban say he is dead - what more proof could you possibly want than the admission of his own Jihadist groups that he is dead.
He is either dead or captured by the US government plain and simple - either one will do for me, I could not care which one of those is true but I think that it is far more likely that he is dead.