[SixOfSpades]

He most probably found that info using Infinty Explorer--it's a program that lets you go into any game using the same engine as BG (Icewind Dale, Neverwinter, etc) and look up all the details--ALL of them--on any item, character, or (I think) script in the game. I think this is also how some of the more difficult Easter Eggs became known to the general public, such as the RoW at the Friendly Arm and the Vampric Sword.
SecretMaster, there is probably no way you could get that ring, as it's almost certainly designated as a "Non-removable" item. There are a few characters in the game that have certain magical effects: For instance, Slythe in the Undercellar is under Blur and Haste, and it's NOT from a spell--if you wait for it to wear off, it won't. He's wearing magic rings that give those effects, and rather than make a Ring of Haste available to the players, BioWare made the rings "Non-removable," which means they can't be taken from him, even after he's dead.