Hi Jd I know I'm new to this but I've been reading and paying attention to where I find ginseng. Not that I've found very much, I have found a lot of the companion plants though. I do have a suggestion check the ground when your out is it really dry or is it wet and moist. Might try digging down a little maybe and inch or two here and there to see how dry it is.
As to how to find a north facing hill my husband bought me a compass because he was afraid I would get lost. I thought that was funny, anyway if the compass is pointing north just turn around, that's what I do, GPS does NOT work out here.
Don't know if that helped or not but good luck.
Anita