Pat, by the end of June, I should have reviews on several campgrounds posted on the forum for our trip down the Oregon Coast through the Redwoods and into Petaluma/Sacremento.
Right now I have reservations for the following:
Cape Perpetua (OR)
Sunset Bay SP (OR)
Prairie Creek Campground (CA-Redwoods)
Hidden Springs Campground (CA-Humboldt Redwoods SP)
Patrick's Point (CA)
Harris Beach SP (OR)
Carter Lake (OR)
Cape Lookout SP (OR)
Might give you some ideas of places. I haven't stayed at any of these yet, but picked them based on lots of recommendations, as well as the activities in the area (tide pooling, hiking, etc). Not sure when you are planning to head out, but with summer, reservations are almost always needed (everyone gets out of the city it seems...especially on the weekends!). Plus, this is the time of year people all are heading North (when we have summer, the Northwest is pretty amazing).
We are also doing a weekend camping trip with some friends for the OMSI star party (our science center holds these campouts and teaches folks about the stars), where we will be staying at Stub Stewart SP at the end of June as well, in case you need something closer to Portland. If you have any questions about the Oregon part of your trip, let us know. Lots of folks here should be able to help!