If your at the end of the valley where the Hungry Spirit spawns, looking at the treants that spawn in the clearing below the hills, take a right and go up the hill. On the last "step" of the stepped area just at the opening into the clearing you will see 3 "static if i remember correctly" farmer spawns. He spawns from one of these.
Not super hard solo as a nec, range attacked, never caught his spells.
Took me 2 rounds to spawn him.. Might not be that rare.