I would start at the beaches for SRC's rather than drive 40 minutes, but maybe thats just me being lazy. Lincoln Park, Golden Gardens, and Carkeek can all turn out fish.
Also the Cedar river down here in renton, there is a thread a couple below yours that talks about it. With it being this hot you dont really NEED waders. I try not to ever wear mine, I have some wet wading shoes and "seal skin" brand socks that get me through June-Oct without waders.
Ahhhh - I've been kind of an asshole lately so I'll try to be nice for 5 minutes.
You're going to really like that sage vantage rod. I have one and have been really pleased with it for tossing dries in particular.
The question is - what type of fishing are you really going to get into? SRC from the salt? You might want to get a longer rod to give you a little extra distance. Steelhead? You're going to want to get a totally different set-up - I'd recommend a 6wt switch, but that's just me and there's a ton of other opinions. The cool thing about the 6wt or even 5wt switch is that it'll be a great beach rod, trout rod, and summer run steel rod.
Trout fishing near seattle in the rivers is somewhat limitted - you have the cedar, snoqualmie, and yakima systems. Neither of those rivers are secrets and a 9ft 5wt is perfect. 6wt switch would be a bit of a bitch to work through the brush, but you could do it.
Start somewhere and buy the rod and all your flies from the same shop. The guys at Avid Angler in Lake Forest Park were super helpful to me when I was getting started. They have a trout tactics class that will literally save you years of shitting on your own hand. First thing you need to do is take a class from a shop.
Red's fly shop in Yakima probably has the best classes around. They have a 101 - 201 and then it splits off from there. They are great teachers and the classes are wildly affordable.
And yeah - this time of year you can save some cash on waders by wet wading in the rivers.
When it gets too, cold drop some coin on some shitty cabelas waders. Treat them gingerly... like a pair of white church pants. Then, when you're completely addicted, dreaming about trout hitting your perfectly drifted size 22 dry fly, you'll go without eating for a couple weeks and get a pair of $440 simms so you don't freeze your ass off.
There are actually spots on Highway 2 where there are pullouts and easy river access to the Sky. I haven't fished the Foss or Tye, I'm sure someone on here can give you details.
If you do decide to get into a bit of saltwater beach fishing for SRC and coho, yes you'll want some waders, not only is it cold, but you'll want to wade out a bit to extend your casting distance when the coho pods are running 100' out. The SRC are typically in closer and you could get by staying right on the beach. And, if you eventually go that route look at the TFO TiCrX Lefty Kreh 6 wt - it's the affordable fast action beach-fishing cannon that I'm sure pretty much anyone on here would give two thumbs up to.
If you like fishing creeks send me a PM and I'll give you a couple tips on smaller water that's really fun, and not tooooo far away nor secrets that would ruffle feathers, but are best kept to a limited audience.
Before going off wildly for flies on ebay, browse the gallery here. Pay particular attention to the fly swaps. Match your fishing type to the flies in the swaps. That way when you are ready to get some flies, ebay or local shop where you can start building a relationship with folks in the know (sure I'm a fan of local shops and you won't go broke buying a hanful of flies) you'll know what flies to get.
Search, search, search this site. Read, read, read what others have said. There are a few "what are your top ten flies for..." or if you can only fish one fly/ten flies, what would they be type of threads that will flat out name the flies you should be using for a particular type of fishing.
Ask questions, mostly of JesseCFowl, becasue for some reason he's already being helpful to you, normally he's just a big bowl of crabby flakes.
Thanks for the replies, really do appreciate it. I looked into both SRC in the sound and also a steelhead setup but I settled back on the vantage 5wt rod, mainly because I will use it in more scenarios. I visit oregon quite often and the lady's father loves having someone new to fish with and I know that rod will be great, plus he was actually the one who recommended it when I asked him where to start looking. Also it adds to the whole future father-in-law bonding thing which is invaluable. So basically, the 5wt seems pretty damn versatile so I can use it for a long time. Also the rods that I've been using of his are 5wts so I feel comfortable starting there. Later when I know more about the limitations of that rod I can add another rod and go from there depending on what I find appealing then.
As far as fly shops go, how are the prices compared with the hundreds of internet vendors? I'm over in Bellevue (about 2 minutes from Bellevue Square mall) so LFP isn't too far from me...altho that 520 toll is really annoying these days. I went to a few in Bend, OR last month but was only shopping for some flys so didn't really notice any price differences.
Also I picked up a delorme atlas of washington and have been looking at the tribs of the sno/sky rivers...not to ask a really, really dumb question but how hard are access to the rivers like the foss and tye (I think I'm going to head out there first)? Seems that the roads (with the exception of highway 2, which I assume you can't just park your car on and hop down to the river?) that get you closest to them are all forest service roads, which shouldn't really be a problem in my jeep that has 4WD but the last thing I want to do is drive the 70+ minutes out there and then not be able to get down to a flat part of the river....The only time I've driven over that way has been during the winter to snowboard at Steven's Pass so the last thing I was thinking about was parking to go fish...