NP- I know nothing about centerpin or spin fishing up there, I'd be just as interested as you are to find out more
Timetable? Fall is salmon... Chinook, coho, chum (I think) and the occasional Atlantic. Steelhead are in the winter... Peaking in Feb from what I've heard (and experienced!). There are summer steelhead as well, I've never gone after them though. This time of year you also have a chance of tangling with some huge browns- I've seen ~8 lbers caught there. Beautiful fish, kiped out males.
For a noodle setup I can't imagine that you would do much different then fly... Really light main line (~12 lb mono?) and probably a 6 lb leader. But someone with more experience than I could probably fill in.