AFAIK, and according to people on the WA-CCW list, it doesn't matter which county you go to. Pick one. In fact, the one to pick is whichever county Astoria is in, you know, theone where the sherriff wants to form a county militia of all the gun-owners, for Homeland Defense...
I have also been told that the "References" requirement is usually ignored, if it even really exists.