We stayed at Black Canyon Campground for one night en route to Crater Lake.  It's a pretty campground with 75 sites nestled between Highway 58 and the middle fork of the Willamette River in the Willamette National Forest near Oakridge.  Since we stayed in October, most sites were available and we chose site #44, which was nice and level.  Though we could hear a little traffic from the highway, we could also hear the river and enjoyed the river access trail at the back of the site.