Birdaddict,
I've just joined this forum but have already read through a lot of postings. I suspect one will get a lot more feedback asking "how" vs. "where." e.g. see posting titled "burned" in this same section.
In that spirit, you want to get up high on the rocky ridges. You find plenty of those along the Columbia, Yakima and Snake rivers. Be in good shape, bring water for you and your dog & have fun!