I just recently leveled a new worgen hunter to 20 and could not find a place to train the dual wielding skill. Prior to 4.0 changes hunters learned the skill from weapon masters but I could not find these npcs in game anymore. The hunter trainers also do not teach the skill.
Currently there is a bug that prevents Dual Wield from showing up in a Hunter's Spellbook. It is possible that you may have it already. We'll look into this problem with it not being trainable, but can you check to see if you can Dual Wield? Thanks!
