Try Carribean Cruise.
Friends of ours went last year on P & O Arcadia to Caribbean over Xmas/New year, advised fab ship, no children, woud recommend to anybody.
I would suspect you have missed the boat here (excuse the pun) as generally all balconied cabins on P&O Christmas/New Year cruises to the sun are sold out the year before - particularly on the ships going out from Southampton. P&O have two ships each year going to the Caribbean and the Canaries out of Southampton - Aurora and Oriana alternate the routes.
It is worth booking as soon as the brochures come out (i.e. the brochures for 2008/9 came out last April) to get the cabins you want. We have been on both ships to both locations (prefer Caribbean - longer and hotter - if you have the time).
We generally book a suite or mini-suite and the prices and OBC if you book early are really good. The atmosphere and Christmas decorations on board are fantastic. This year P&O are also offering free parking at Southampton (worth about £150)if you book before 31st August.
The Fred Olsen Line do a cruiseto the canaries over the Christms period, and I can recomend them I will be going to the Baltic in September my third cruise this year small ship good food. and good servic.
P&O Arcadia ia a "Child Free" ship we went in may for our 1st ever cruise....it was great! The food is fantastic, but be warned, you WILL put on weight!!! We have no children & the only ships we know of to be child free are this one & ARTEMIS P&O's smallest in the fleet! Arcadia is large at 83,000 tonnes. They really do go the EXTRA mile to look after you & many people who had done 20 or more cruises say exactly that! Happy Cruising!
Try Cunard's Queen Victoria maiden voyage Canaries and N.Africa etc - out of S'ton 16/12 and back 16 days later. They still have a few s'rooms on offer. It will be etched in your memory for years to come..
You won't be able to go this year - far too late. We've done Arcadia and Oceana over Christmas/New Year in the Caribbean - it is great - this year taking the family including teenage grandchildren. I have friends who booked for Christmas 2008 about a month ago and could not get the grade cabin they wanted (I am talking P&O - may be different on other lines). It is a great experience - hope you enjoy it.
Arcadia - is kid free and usually does an itinerary to panama canal etc - recommend it.
Try p&o.The acadia has no little devils on board.They do cruises to the carabbean which are outstanding.the service is first class .You wont be dissapointe.
Agree with other comments, doubtful if you will get a cabin with a balcony this late. P&O Arcadia or Artemis are both adult only and can recommend either. Artemis being smaller is perhaps less daunting for your first cruise but Arcadia is newer. The food, wine and service is excellent on both. However they get full very quickly and we are currently looking at late 2008/early 2009 to get right cabin choice. Have a great time.