I finally picked up a quality atlas of Oregon. I debated between a few choices and settled on one from the Benchmark series. I'll be picking up the rest of the series (AZ, CA, NV, UT, WA).
Here's a snippet from a section west of Portland, OR. (I blurred the edges for better image compression).
And attached is the top left edge of the same page, showing how they've rendered lat/long for the GPS user.