Man,
I was only there once back in the late 70's was TDY at Yakima. On the coast highway there were about a million small streams running down to the beach. We just stopped in some of the little towns, asked a few questions and went out and fished. I imagine most of that water is private now. But it won't hurt to look. Some of it is/was federal land. Ya roll the dices and ya take your chances. If it was me I'd check some of the small towns for tourist info. As for camping... take scuba gear. It's a rainforest. Stay at motels on the coast. When you go up the Columbia it is high desert. Great camping. Sturgeon, The Columbia is loaded with them. Hire a charter and go for it. I think the pinks are running about this time too. But I could be wrong. Try Google Earth. Pick a small town and do an areial of it. If it looks fishable, research it. If it has fish Plan it!
Illegitimis Non carborundum