Boy are things different in competition. Peaches is really fast and can turn on a dime and very responsive to what I tell her. She can be stubborn though. I bet she would something in it.
At least around here, it's very reasonable - $60 for 8 weekly lessons. Entry fees are typically 10-12 bucks per class, with a discount if you enter a large number of classses (in USDAA - AKC there are only two classes - standard and jumpers). Or you can just find an agility trial near you, and go wander around during the day and chat people up and watch the competition.