Well, it does depend on when you are sailing, since hotel prices are dependent on the season. You could always check Priceline and Hotwire and see what you can find for your date. Just be sure to check TripAdvisor. Aim for at least 3.5 stars.
Disney Dream - Dec 2012 4n Bahamas
Carnival Imagination - Dec 2011 4n Western
Carnival Imagination - Nov 2010 4n Western
Costa Atlantica - Dec 2009 7n Eastern
My opinions are mine and mine alone. They do not represent the opinions of The Walt Disney Company nor any of its subsidiaries.