I think the need is relatively low due to being able to spar on alt characters for training. There should be some, I just don't know where. Sorry. Also, search the forum, I think this topic has been hit before.
We will be slowly adding them into the world over the next few patches, most were disabled due to problems with their default coding. Once we finish a review of their design we will slowly spawn hire-able npc's into the various locations you would expect them. Blaise is correct however, you can train on your own characters just as effectively.
