Armoralleather is good, but I want to mention that Jeff Law (forum name: Rainwalker) has an outstanding reputation for the quality and artistry of his sheaths. I don't know how busy he is at the moment, but he's a great source for leather and kydex sheaths. There are a lot of other guys, such as David Brown, who posts on the forum and is great to deal with too, but Jeff is the gold standard in the Yard -- give him some time to be artistic and he'll make you a work of art.
