We found AirLink Shuttle to be excellent. In the baggage claim area at LAG there is a dispatcher person who will call the shuttle for you. It will take you to the cruise terminal. Cost about $15 pp. They have a website you can check out. A cab would be quite expensive.
50 Carnival: Mardi Gras, Ecstasy X2, Fascination X6, Celebration, Elation X5, Glory X4, Fantasy X4, Valor, Holiday X3, Imagination, Liberty, Spirit X2, Freedom, Destiny X2, Splendor X2, Dream X2, Conquest, Legend X2, Victory, Sensation, Paradise, Inspiration, Magic X2, Triumph, Miracle, Breeze
6 Norwegian: Sky, Jewel, Dawn, Epic, Pearl, Breakaway
6 Windjammer: S/V Legacy X3, S/V Polynesia, S/V Caledonia, S/V Diamant