How do you get a specialization in Dragon Age Origins

Wait until level 7, then you have to do one of the following.

1)Buy a tome.(Easiest but most expensive)
2)Ask a party member to train you in their specialization.(2nd easiest, but limited.)
3)Find an NPC to teach you.(VERY VERY HARD, but free, and not that limited...)(i.e., desire demon in the fade teaches you blood magic if you're a mage.)


That's all that I know.
-Neo