[Keeper of Dol Guldur]

I think I would like to point something out.

This adds to the first post, in that I also agree that in some form or another, the mortals who were accepted into Valinor gained immortality.

In every case in the Lord of the Rings of mortals given entrance to the Blessed Realm, that privilege was given to them by an immortal.

This is very easily recognizeable in Frodo's case.

Arwen literally gave him her immortality.

This was represented in the form of a symbol - the jewel that she gave him. She foresook her immortality, to remain in Middle Earth, and that left a slot open on the last cruise ship to Valinor, so to speak.

Now ... that was the case for Frodo. But it could be that this afforded all the Ringbearers with this chance to go.

I've heard somewhere (and this is very vague, and probably unsubstantiated) that Bilbo was able to go, because Thranduil foresook going into the west, and remained in Middle Earth, where his great store of wealth, rivaling those of the great elven lords in Middle Earth, in the elder days, was, content to stay.

He really thought Bilbo was an amazing fellow, and was the one who named him Elf Friend if I'm not wrong ... after Bilbo took such a huge step in solving the dilemma between Thorin and the people of the Desolation of Smaug, and smuggled the Arkenstone to them.

I have NO clue where I heard that. Maybe my old English teacher mentioned it.

But, that doesn't explain Sam, or Gimli. Although Tolkien made a point of saying that Gimli was a very special circumstance, and that no one had ever seen a friendship of the sort that he and Legolas had. (In a strictly platonic way, by the way).