Go to your local non-profits and offer them your services for free. Be clear that you're just learning and that's why you'd make them a web page or an intranet app for free. You'll get to learn, some feedback, more or less honest customers and karma points. Once you got experience and portfolio, you can go after the better paying projects (~$10/h or so) that are run by sane people who will treat you well.
Source: Started freelancing back in high school, almost 10 years in business.