Hello Pat. Fort Stevens is a good choice, also just south of Tillamook is Cape Lookout state park. Stayed there last year. Somewhat off the beaten path, but a great beach and very quiet. A few large spaces, if that's what you need. Also, at Barview, there is a county park (Tillamook county) that has several sites. It's older, but kept up well. It's right next to the jetty, with lots of fishing boat action, plus the coast guard maintains a station there. Another one that is a favorite, but not at Mt. Hood or the coast, is Memaloose state park up by the Dallas. One of the oldest parks, but is in good shape, and is very nice. It is an "annual outing" place for us every year, to start the season off. Check out the Oregon State Parks website. It will tell all........
Hope that helps.