Speak with Historian Karnik in the Hall of Explorers within Ironforge.
Greetings once again, [player]! Your discovery inside Uldaman has set the Explorers' League abuzz with excitement. The League has been working to unlock the secrets of the miniature platinum discs you found. Your fortuitous arrival here in the Hall allows me to share with you that we are quite possibly on to something!
Historian Karnik has uncovered some important clues as to the true origins of the Valley of the Watchers in the Tanaris desert. He would like to speak with you as soon as possible!