Shore Excursions-best to book thru RRCL?

I am going on the Mariner on June 4th and we are considering several shore excursions....swim with Dolphins, horseback riding, zip lines. I have read that it can be quite a bit cheaper (and a better tour) to book directly with the tour operators. I am worried about what would happen if the ships itenerary was changed (ports cancelled, etc.) Would I lose my money if I didn't book through RCCL? What is the best way to
find tours to book direct?
Thanks,
Trish

[georgi]

My boyfriend and I found last year on our cruise it was cheaper to do things on our own rather than book them through RC. Buy a couple books and do some research before you go. We found the "Fodor's" books to be very helpful.

[Sonny V]

I always book on line. For example when we went to belize we want to do cave tubing. I did a google search which brought me to the site where I booked the cave tubing. I save $35 per person from the ships tour. Ship tours are usually more crowded. You will love the Mariner! We just got off the Adventure 3 weeks ago. Been on all of the RCCL ships.

Have a great cruise!

Thanks. I think we will book our own tours based on the comments above. Our cruise isn't until June and I can't stop thinking about it already!