Sidetracker,
We were on the Carnival Spirit this summer to Alaska. They have a shore excursion info night, 1st night I think, and you can fill out your shore excursion requests there. At this meeting, there were not very many people, and we got everything we wanted. You give your order form to the people there and they were very helpful as well.
I'm sure glad we went, because there were plenty of people on day 4 still booking excursions.
Hope this helps.
:CAN