Hagg lake has large mouth if you know where to look. The place I would fish is either sain creek or the dam. Spinnerbaits in the spring, senkos anytime, nightcrawlers work too. Crankbaits work well sometimes in the fall. Fish the senkos weightless, then let them drop to the bottom, then reel em really slowly. Willamette has LM bass if you dont know, just not as much as SM. Multnomah channel has LM bass and SM bass. Erm... Oswego lake has panfish, SM and LM bass, but it is private and the only way to access is through a friend or off a bridge. Tualatin river has some LM in it, but you'll catch a sucker or squaw most of the time...
LM bass will take almost everything that a SM will take. Senkos, crankbaits, plugs, grubs, nightcrawlers, spinnerbaits, spinners, spoons, and so on. They arent that picky, so just experiement is what I'll say.
There are ponds everywhere further south around salem and eugene that have bass, like wilsonville pond has some LM bass, then theres a lot more little ponds that people have explored and found bass. Good luck and happy bass huntin!
