Okay, since the Location is somewhat difficult to track in a Dungeon, I figured some landmarks might be helpful. Pozlin is located in back of a shop called "More Than Mushrooms." After making your way into the city proper, Head down the ramp with the windows, under the wall with the gargoyles, and into the marketplace. There will be a couple constructs patrolling. Head past "The Slab" and make a left at "Coranier's Clothing," then right, through the wall. As you pass under the wall, you will be standing before another building. Follow the alley around to the left and deal with the constructs that patrol there. "More Than Mushrooms" is just beyond and Pozlin is inside, along with two more spirits, in what appears to be an herb garden.
If you stand at Coranier's Clothing long enough, you'll hear him start casting spells. After I'd done my turn in, my monk friend, whom I'd brought along for some added muscle, killed Pozlin out of frustration at not being able to find him sooner. He then respawned no more than five minutes later, so he should always be up.

