MissyD,
Venice, and
IK have given very true advice above.
First of all, I just heard someone saying that hotels are crazy packed the 1st 3 weekends in September and I don't know why. Some other possible hotels downtown that I can think of besides the main ones and boutiques are the Best Western in Pioneer Square and the Ramada Inn on 5th and Lenora (or Blanchard?). The room rates there will easily be 1/2 of what else you're seeing.
If those fail, there is also a Hampton and Homewood Suites (if you're looking for a chain), in Lower Queen Anne which provide easy access to Seattle Center (Space Needle, EMP, etc).
Originally Posted by IK in Seattle
My 2 cents would be to try to get a room downtown on Priceline, you should be able to snag a 4* around $125. With regards to the car, you could rent a car from one of the downtown car rentals agencies for a day, and that way avoid the very high parking fees. I know Hertz has a place in the same building as the Grand Hyatt, and I’m sure there are several others. As far a downtown being pedestrian friendly goes, Seattle is hilly, but the buses are free in the downtown ‘free ride’ area
There is also an Avis @ 5th & Virginia.