Thanks for your question about worm composting (vermiculture)! First, here's a link to a nonprofit that lists some earthworm sellers in your area that I found but you can usually get them for free on Craigslist and Freecycle. You only need 500 or so (which run between $15 and $20), to get your bin(s) started, and, if they're happy, they'll provide you with generations more worms!
Second, here's a link to an OSU publication that pretty much covers the same subject, but from an academic perspective.
I'm sure anyone listed in the first publication can answer questions, and there's always the OSU Extension Office in Redmond: 541-548-6088.
I keep two bins going continuously, and my plants adore the 'castings!' Good luck!