In Keizer (and there's members here very familiar with the area, and they're helpful folk), you're somewhat limited compared to other locations. Locally, you have little-to-no catch-and-keep opportunity right now. The few steelhead are mainly natives. As spring progresses, there will be opportunity for spring Chinook, although heading further down the Valley will offer more.
Right now, there's steelhead opportunity (when the water drops, anyway) at the coast. Check out the Salmon, Nestucca, or Siletz as your closest choices.
Are you boating or banking it? In the coming weeks, the Portland area has a bunch of chances at spring Chinook, but it's much easier done from a boat, and there's a tough learning curve, and it can be a zoo (not that there isn't plenty of water, but people crowd the hotspots). The coast offers very limited spring Chinook fishing, but it's around the same time as the summer steelhead runs (the numbers of which vary radically every year, sometimes great, sometimes a disaster).
But in the short-term, the coast is your best bet. Nestucca isn't too bad a run from Keizer (22 all the way out).
Hope that helps until the Salem area OFFers can chime in with their expertise.
