Cityleague @ The Summit / Alpental
One nice outlet for rec ski racing in the Seattle area is City League. They run dual gs-like courses head to head evenings, Tues., Weds., Thurs. at The Summit at Snoqualmie, and Tues, Weds., Thurs. & Fri. nights at Alpental (each night is a different league. For example, I'm Thursdays at Alpental.) There are about 120 racers per night, so the total CL community is probably about 1000 racers all told. It's a 7 week series.
It's very fun and can also be as competitive or laid back as you want it. The top racers in each league are FAST and are going for it hard, and the rest are having a good time trying to improve and hang with their friends. You're paired with racers who get similar times as you throughout the season so you can always race for a win. Your team gets points for you beating your paired guy, and also for the lowest combined times.
Here's a link:http://www.cityleague.com/