I can be reached through my website, newmoonbirth.com. I am a doula, cbe, ICAN co-leader and work with a lot of vbac mamas and students. I live in Seattle.
I would second Sharon above as a resource. I do not know of any on-line resources for finding a VBAC friendly provider from when I was looking just over a year ago.
I think Group Health Central and The university of Washington are the most VBAC friendly hospitals in the Seattle area. If she doesn't mind seeing a resident for her care, she shouldn't have any problem getting an appointment at UW. There are also a lot home-birth midwifes in the area who will do VBACS.
This link lists several midwives in the Tacoma area. They wouldn't be able to catch at the Birthing Inn, but they might be willing/able to help with a home birth? http://www.thebirthinginn.com/about_staff.html
A friend of mine in the area is a midwife and highly recommends Dr. Luba Foltz (http://www.seaobgyn.com/foltz.html). This midwife has observed the doctor on transfer from a difficult home birth as well as during a VBAC. Might be worth asking around to learn a bit more about her.
Take a look at the Great Starts/Parent Trust website and download their Healthy Birth Guide to King County. A new version is also coming out in the next few months. The Birth Survey (www.thebirthsurvey.com) is a consumer reported database of mother's birth experiences and the Seattle area can boast the most surveys taken by women. The Puget Sound Birth Center (located in Kirkland) is the most frequently rated birthing facility in the United States.