You receive this quest from De Menchev, who is in the Board of Gods.
He asks you to go find Merlins book of magical spells.
It was stolen by fairies after a party and they hid it in the Parks Violations Bureau in Boscawen Village.
It may be in their Lost and Found Section.
You will receive the Merlin's Magic Spells quest.
Go to the Bureau of Parks Violations which is located in the Southwest corner of the Village of Boscawen.
Talk to Jobsworth Horn.
You will steal the Official Key from him.