Target monster for the Reach of the Shadow and Siv's Sprirt quests.
Approximate Loc sights (she does roam):
To find Ulga, from Aylarn (in front of lean-to) run west, then you'll see the tower and the camp of Bloodfellags. At the camp take the path and head a bit northwest (maybe a bit more north than west) then we saw her wandering around.
Go to Audliten, go north across the bridge and take a left at the crossroad. Follow that trail a ways until you get to the top of the hill where there is another crossroad. Take a left (If you go right, you will end up at the West Gate). Follow the path until the next crossroad. There are 2 stumps, one on the south side of the path and one on the north side. If you stand next to the one on the south side and point yourself due South, go forward and you will run into a tree. Just past that tree is where I saw her each time. I hope this helps reduce some of your search time.