I just found this, don't think the most recent one has been covered here (very sorry if it has). This is the Q4 2007 version, released in February -- you have to request a pdf here [http://www.globalinsight.com/Highlight/HighlightDetail2350.htm] and it is e-mailed to you almost immediately.
Their conclusion is that in Q4 of last year Seattle was 30.7% overvalued, fairly consistent with what I daresay the consensus is on this site. What surprised me is that Longview, at 44.2%, and Bellingham, at 44.1%, rank #4 and #5 nationally. Spokane is the only WA market tracked that is undervalued not overvalued. Interesting too to scroll down the list and see where various regions tend to settle.
Bonus: Appendix C, "Past Price Corrections," a nifty historical record.