The book can be found on the shelf immediately to you left
Horde Quests: Death-stalkers in Shadow-fang - Go to Shadow-fang keep to the south and find the Death-stalkers Adamant and Vincent. Find them, and if they require Dofus Kamas aid then give it.
You can find Death-stalker Adamant in one of the cells where you locate the key to enter into the keep itself, he is not marked on our map as you need to go right past him. You can find Death-staler Vincent's body near the beginning of the instance. He is marked with the light blue dot on our Shadow-fang keep map.
The Book of Ur - Enter Shadow-fang Keep and find the book. Bring it to me, and I will report your service to our Dark Lady... The book can be found on the shelf immediately to you left when you enter the round room in the keep where you fight Fenrus the Devourer. He is marked by a green square on our Shadow-fang keep map.
Warlock Quest: The Orb of Soran'ruk - Find a large Soran'ruk Fragment. This quest also involves a trip to Black-fathom Depths. The part you need from SFK is dropped by the Shadow-fang Dark-souls located throughout the instance.
