There is a Red Lion Hotel @ 11244 Tukwila International Blvd. It is about 1/2 way between the airport and the terminal. They will shuttle you to their hotel from the airport and again to the terminal.
Restaraunt has very good food and the lounge pours a healthy drink with lots of tv's to watch.
Cost me about 80.00 2 years ago.
There really aren't any hotels any closer to the cruise terminal.