check out
www.vrbo.com. In case you don't know about it - it's a site for people to rent their own places out.
It'll end up saving you quite a bit - when you don't end up paying the hotel $20 for parking and 18% hotel tax.
I found these listed there
http://www.seatoskyrentals.com/
Here's a hotel that looks nice/affordable and is with in 3 blocks of the downtown shopping area. 8-10 blocks to the fish market aka pikes place market
http://www.vancehotel.com/
---Here are two bed and breakfasts that sound nice. the first is in the heart of the lower downtown/classic old seattle. the second would be a little walk /short cab to downtown. so less ideal if you plan on bumping around downtown
Pioneer Square Hotel
(206) 340-1234
Capitol Hill Inn
(206) 323-1955