In Neriak Third Gate: Noxhil V`Sek is found on the top floor of the Lodge of the Dead. If you ask him, "Who is Innoruuk," he mentions the Scroll of G`Han, which was scribed long ago by the great necromancer G`Han and was used to communicate directly with Innoruuk. The second half of the scroll, however, was apparently stolen by a rogue hired by the Koada`Dal and now lies within Felwithe.
In Neriak Fourth Gate: Spawns just north of the portal stone to the Ethernere Tainted West Karana (click for map image). For all things related to Call of the Forsaken, check out this overview of the expansion.