There are pleanty of places to catch nice size trout here in Oregon. They just arn't close to the metro areas. Look at the successfull turn around of Diamond Lake. It's a great place to fish and if you do a search there are a few threads with pictures of some darn nice fish. If you want big fish and no power bait head over to the Deschutes. That river was being fished out and ODFW had put a lot of hatchery fish in it. Now they have a 2 fish limit with a 10"-13" slot limit. Anything over or under must be released. Now the Deschutes River is a great year round fishery with tons of public access.
If you head over to Central Oregon hit the lakes south of Bend on Century Drive like Lava Lake, Craine, Elk, Todd, Davis, or Cultus. There are threads on here just recently with pictures of Cultus Lake . I used to fish Antelope Flats reservior up in the Maury Moutains just south of Post and would get into some scrappy rainbows. Venture over to Chickahomny east of Bend by Glass Butte after ice out. You'll find big hungery rainbows. If you go further east check out the Donner and Blitzen River or Fish lake over in the Steens Moutains, another thread on here. I haven't fished it yet but I plan on making a trip to Mann Lake on the east side of the Steens to catch some of the Lahotan Cutthroat they have there.
I just fished the Crooked River over by Prineville. I only fished for a couple hours caught three fish one of them was over 15". That's a lot of fun on a 5wt fly rod.
The problem with fishing around the metro area is the amount of pressure on the limited fishing areas. When Timothy (Meadows Reservior) Lake and Harriet were built as a water storage areas for PGE's dams on the Clackamas, the population of Oregon wasn't quite a million. Now our poulation is over three million and the access to places like Harriet is a lot easier than it was back in the 40s. So there are a lot more folks fishing those places and if they didn't stock them there would be no fish there at all. Remember the reason they quit stocking the river and started to stock the lakes was to make the lakes a "Put and Take fishery" and have the rivers be a place to establish a non-hatchery fishery and at the same time take the pressure off the salmon smolts.
Oregon has always looked for ways to increase the fishing expierence. Like putting Atlantic Salmon in Hosmer Lake, introducing the Macinaw (lake trout) to some of our lakes like Odell and of course planting all those brook trout that they are trying to get rid of. About 1992 they started planting steelhead in Lake Simtustus. There is not a lot of pressure on those fish and you can catch them in the 14 to 15 inch range now fairly often (another thread on here). The trick is to get away from the metro areas.