An interesting thing to note about the rares in Arathi Highlands, is that none of them actually patrol around once they've spawned in.
Kovork can be found at the end of the cave at Boulderfist Outpost. Geomancer Flintdagger waits at the end of the cave east of Hammerfall (Drywhisker Gorge). Zalas Witherbark can be found just inside the cave at Witherbark Village.
Prince Nazjak has four different underwater spawn points in Faldir's Cove, but once spawned in he doesn't patrol between them. He can usually be found inside one of the sunken ships.
Singer can be found inside the small house at Northfold Manor staring at the fireplace. Be careful when engaging her on low level toons, and ironmen toons especially - she has a mind control ability and she can and will use it.
|Click map to enlarge|
Screenies of each rare in order by level, and exactly as you'll find them in the zone:
|Darbel Montrose, Kovork, Molok the Crusher & Nimar the Slayer|
|Foulbelly, Singer & Zalas Witherbark|
|Prince Nazjak, Geomancer Flintdagger & Ruul Onestone|