We have been all over Oregon. If you can find work near the Bend/Sisters/Prinville area I highly recomend it. There is a ton of BLM and National forest land in the area. The public lands are very close to the towns and very easy to find free camping with good cell phone coverage. Also everything is really beautifull in that area. We spent about 3 months there last summer and loved it. There are free dumps in prineville and the cove palisades, and nice showers for $2.
I also love the brookings area, the coast in between brookings and gold beach is my favorite stretch in the whole country, and we have driven just about all of it. You can boondock on any coastal pull out in oregon as long as there is not a sign saying otherwise. There is a time limit, not sure what it is but I don't think anyone is really paying attention. Just switch up the pull out often, there are many, and you will be fine. There is also a very good dead end in town, on the brookings side of the river that is in between harbor and brookings. Drive down the side street to the river, its a quiet dead end that I have used several times and never had an issue. I have not stayed in the spot more then one night at a time though so keep that in mind. They have a free dump at a rest stop on the north side of brookings. It's not a huge town, but big enough to find work in, at least it was for me I really don't know what your trying to do for work so YMMV.