Who, in The Lord of the Rings, was the most effective liar?

[Alfirin]

I though I should point out that Saruman gets away with another lie earlier in the book one that in its own way is both more audacios and more effective than any he is able to put over on Theoden via Wormtounge. The lie is when he tells the Morgul King that he does not know where the Shire is. As pointed out in the Unfinished Tales, Saruman would have had to know where it was. The agumen made goes something like this. Like Gandalf, Saruman by this tile also used pipeweed (Merry after being woken up by Aragorn and looking for his pipe says that the pipeweed he has is "some of Saruman's best") Since its use is still more or less unkown Tolkein makes it clear that the Shire and its immediate environs is the only place in middle earth from which pipeweed can be obtained. Therefore, anyone who uses pipeweed must have business contacts within the shire, or at least within hobbit lands. This lie is in its own way more audacious than those to Theoden. After all theoden represented little threat to Saruman on his own (i.e. sans ents and hourns) whereas lying to the morgul king if the lie was found out risked incurring the wrath of both the Morgul king (who is proably more powerful that Saruman one on one already by the time of the lie) and of Sauron himself. Even if Saruman was not yet in Sauron's thrall lying to the morgul king would be a risky move at best.