Use the search feature on the 'Buzz, there are a lot of good posts already on this topic from the past. Raft guide training is a great way to get lots of practice, and a short-cut to the basics, but bear in mind that it usually happens in the spring. Also, fly fishing oar cert classes may be better for you since most of the local whitewater outfitters in the Vail Valleyare 90% paddle boating, and their training will follow suit.
Post on here to plan trips. As Andy said, the Upper C is a great rookie training ground. Check out anything between Pumphouse and State Bridge for some good training runs (there are lots more, but that is a good place to start). This is where almost everyone in the Vail Valley learns to kayak, raft, etc. their first time.
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