I am trying to get the doomcallers circlet and am not finding any quests in aq40 and I have tried looking for help on wowhead but to no avail and I was also wondering if a priest can wear the head piece
Doomcaller’s Circlet is part of the Warlock AQ set, so the quest is only available to Warlocks. Priests get Tiara of the Oracle instead.
I think you have to do the “Mortal Champions” quest where you turn in one of the Qiraji Lord Insignias before any of the other quests show up.
But, as Minidecay said, you won’t be able to transmog the Warlock set onto a priest, as the set is class specific.