IH8DrivelinesNW. At least the Everett shop. I've heard better reviews about other locations, but for the price they charge, I'd call Tom Woods or High Angle.
Best Drivelines is in Everett. Greg is a wheeler. (425)513-8182
Cheap prices, decent quality, quick turnaround. I had one shortened, one lengthened (complete re-tube), and both balanced for ~$150. Some people have had poor experiences with Greg, but mine was great. YMMV.
To the south, local wheelers recommend:
Aukeen driveshaft in Kent (253) 395-0392
Dean at Bent Metal Customs
Bent Metal Customs--Official web site for Dean Detweiler, Puyallup WA
Dave at Advanced Driveline in Yelm
Fleetpride in Tacoma
Drivelinetech in Portland
To the north:
Ritch at Driveline Service in Bellingham (360) 734-7828
But seriously, if you can afford to wait 3 days for shipping from Tom Woods, call him and see what his price is. Lots of guys have found a complete new shaft from him to be cheaper than getting a used shaft re-tubed.