Class-tied books and pages (Bullroarer's boy, Way of the Hunter etc.) needed to get them special traits have been selling like mad and continue to do so. You can make 150s-500s per book or page depending on the rarity. A very good way to harvest these once you reach about lvl 50 is to go to Misty Mountains and check out the goblin camps in the middle of the chart (area near the western high pass). Goblins spawn quite often as you make a round-trip through their camps. The much sought-after pages will drop with a rate of about 1 in 10 kills. After collecting about 5-10, go sell em at the Rivendell auction and return to the camp fire in the northwest of misty mountains or Gloins camp to make a quick retry. Happy hunting!