Olympic 4x4 in Snohomish can be a little proud of their pricing. I needed a T-case shift lever and they wanted to charge me for the used part the same price as the dealer wanted for a brand new part. You could probably haggle with them but I'm not sure the drive up there is worth the gas money and time unless you're going to save a pile vs. new parts.
I think there are some junk yards down in the Kent / Auburn area, and possibly out at Four Corners near Maple Valley. There are also some on Hwy 99 north of seattle, IIRC. Best thing to do is crack open the yellow pages and call up the places to see what vehicles they have.
As for used tires. . . again, check the phone book (or online) and call them up.
Oh, and welcome to Seattle.