Here is a download for a good, concise text of the sport by British
coaches, Alan Tordoff and Neil Stamps. Although written for coaches,
it is a great first read to those new to the sport and those of us
that lack years of experience and are looking for new training ideas.
Click on Wildwater Racing Manual in:

http://www.wildwater.org.uk/index.php?option=com_docman&task=cat_view&gid=153&&I\
temid=146

Also, the swimming session workouts looks good for winter workout
without the boat. Since our snow melted, everything is flooding here
in Western Washington. A swim in a warm pool sounds like a great workout.