for Champions:
do the newbie quests up until you get to the basic crafting skills. (i dont know if you can start a bit later, i just did all the quests from my dwarfs spawn point up until i got to him, took me 10 minutes)
then you will have quests from the Runic Craftsman teacher (or whatever his job is called in english, i dont remember. that guy just on the other side of the elite skill master hammering some stuff) - his name is: Logden Darkstove.
TLDR: do the newbie quests until you reach quests given to you by Logden Darkstove. And be Level16+. He will unlock "Shield form". After you have obtained shield form the elite skill NPC works.
I did not try out warlock, sorry.