I would recommend using this Vacations-To-Go web site. Everyone's rates are the same as whatever the cruise line is offering. The difference is that this site gives you all of the good deals by location especially for the next 90 days. They give you the ships rating and the discount percentage for each cruise. Many times you can get 80% off of the rack rate if you book within 90 days of the cruise. I used them for both our Alaska and Hawaii cruise in the last year.

http://www.vacationstogo.com/ticker.cfm?t=y