Hi Again Wendy,
The ship will dock at the Bell Street Pier Cruise Terminal at Pier 66....
When I do my Alaska cruises I always use
Emerald City Shuttle...
You can call them and reserve a ride back to the airport...I think it's around $20 per person...1-888-622-3400.
But there are many other vans and taxi cabs ready to take you to the airport...