I am loving all the Buzz warm responses without the "learn to row, noob" comments! Being humble and asking for help is how we all started rowing, Scott. Also Youtube has a ton of runs of all kinds of stretches which helps learning the rivers and how to approach rapids.
Besides running rapids, a lot of rafting is really logistics and organizing camps. Learning the permit systems, required and safety gear, learning the best camps on rivers, camp logistics, cooking crews and menus. It takes minutes to run rapids and hours to organize a drunken stampede in the camp. Listen and learn from the people who have done it before and your own group trip is going to be that much more enjoyable.