Here's some advice from current grads on moving options, should you prefer not to use the classic method of throwing everything you own into an aging hatchback and driving cross-country:

UW Computer Science maintains an extensive listing of housing & moving information.

"My other main piece of advice is on the housing search. I decided to make a trip out to Seattle to look at places in person, and had originally bought plane tickets for mid-July. However, I was surprised to find that tenants in Seattle only have to give a couple week's notice to their landlord before moving out. This means that apartment openings tend to come on the market at the last minute, so the peak rental availability for the academic calendar is actually early August. I decided to change my trip to the first week in August, and I saw many apartments and ultimately found a place. It's kind of a scramble because all the other incoming students are looking for housing too, but I think it was worth waiting for more apartments to come on the market."

"When I moved here from Boston I ended up using UPS. If you send your boxes from a UPS store directly to another UPS store the rates are cheaper. I ended up contacting the UPS store in Wallingford and they were able to store my boxes for about a week while I traveled out here. I don't remember the price being exorbitant but it wasn't super cheap either. I do remember that the folks at the Wallingford UPS store were super nice about storing my boxes though."

ABS freight:
http://www.abfs.com/Default.asp?bhcp=1