Several channelers are communicating with him. Birgit Klein probably is the most famous one. In channelings, he is often referred to by his Latin name of Germanus.
According to the legend, the count of St. Germain never died, but was taken (ascended ?) directly to heaven, after having walked the surface of the earth for over 300 years.
He is said to be the Lord of the Seventh Ray, and, rather exceptionally, on this all authors seem to concur.
Previous incarnations may include Lao-Tsu, Montaigne, and Francis Bacon, to name a few.
Saint Germain also was one of the main guides of Madame Blavatsky. (See Theosophy for more information).
Note that Saint Germain is his full last name, and that he was not a saint whose name was Germain.