Hi elated, welcome to Cruise-Chat! Congratulations on your up-coming cruise! What a wonderful gift for your mom, do you want to adopt me
Wish I could help you with excursions, but have not sailed to Alaska. Since I abhor cold, I doubt I ever will. There is an Alaska Port section just a little further down the main page that may be of benefit. You can use your "Find" feature in the upper left hand corner, type in your ports, click on search and it will pull up all the posts made about them. You might be able to find something that interests you.
Hope you and your mom have a wonderful time and enjoy Princess as much as my hubby and I do. We have quite a few members on this board that have done the Alaska itinerary and they'll be happy to help as much as they can.
Best wishes for a wonderful cruise!