Regarding the question of whether Sauron had the Ring with him in Numenor, there is a nice thread from some years back on this issue (in which I made many of the same arguments raised here by Gordis
). This thread can be found at the following link:
http://forum.barrowdowns.com/showthr...n+numenor+ring.
To put that thread in context, that discussion arose at around the time when various members were debating the relative "reliability" of sources outside the primary works (such as
Letters, HoME,
Unfinished Tales and even whether the Silmarillion should be considered a "primary work"). While the letter quoted by Gordis and the other letter quoted in the linked thread seem absolute, there is some text that suggests or implies that Sauron did not take the Ring with him to Numenor, and there exist valid arguments that this was the case if one chooses to discount the letters.