Easiest is Supershuttle, just get your bags and head to one of their stands no reservation needed. Last trip I was immediately put in a town car and left, no waiting to share or anything. I believe it was $23 but you can check and see if prices are the same on the web.
11 cruises in 2012, 90 nights at sea visiting 15 countries
8 cruises in 2013, 56 nights at sea visiting 7 countries
Next cruise: None scheduled
PM me if you need a cruisemate for any Europe, transatlantic, or Panama Canal cruises
Date, ship, cost pp