I had trouble finding out where the quest started. I went to Giran, but thats where you go if you want to become a Soulbreaker.
After going to all the towns I figured out that you have to talk to Olkrus, who is at the Kamael guild in Oren Castle town. Everything after that is really self explanatory, it tells you were to go on the map.
I just thought I'd share that with everyone because I couldn't find anything on the internet!
... for future refrences , make LOVE to your world map.
Open world map - > quests , level 39 , ceretificataion of beserker - > name of NPC and town.
You can do that for any quest in the game, also for raids, i am surprised at the fact that in raid parties people don't know how to scout raid bosses even at 60+ , come ON 60 lvs into the game and you don't know world map tells you where each boss is ? COME ON