ST - Metro Publication (Sound Transit) provides transit services in Washington.
Sound Transit Online
Online includes: Real-Time stop predictions (Bus, Tram, and Ferry). Trip updates (Bus, Tram, and Ferry). Sound Transit On Twitter with the all lines option (All Travel Modes). Vehicle locations with per stop, per line, and per direction options (Bus, Tram, and Ferry). Sound Transit On Facebook. News (Tram).
You can access any of these services from Stop Times, Route Map / Vehicle Locations, or the Online area.