Marymoor is in Redmond, about 1/2 hour drive from Seattle. Or you can ride on the Burke-Gilman bike trail over there, about 50-60 miles round trip depending on where you start.
There are newbie races on Monday nights, more experienced races on Wed, but the real show is Cat 2-3 races on Friday night. Women's training is on Tues night, and another open training class on Thurs night. Their loner track bikes are available every night but Friday. If you go other than these times you have to bring your own rig.
That said, I've been going out 2-3 times a week and I'd be happy to bring you with! The Tuesday women's training is great. Let me know when you're coming out and we can hook up.