Kill the Gnome Wizard in the hidden tower in Nibblemheim for the reward (need deathblow for the quest reward, but everyone can get the scroll)
Go to Nibblemheim (go east out of Hamilton hold, then climb gate, (bring a rope), follow the path, then "hurl hook" at the dead end. keep going and go "ferry", then south)
Inside the city, go west and south into the guard tower,