Some things to remember, if you're a guy:
First and foremost, don't neglect your grades in high school. There's lots of money to be had via academic scholarships, grants, etc.
Second, don't forget about other scholarship opportunities like FastWeb.com. You can register to receive updates on all sorts of scholarships that are available.
Third - there is actually quite a bit of tennis scholarship money out there that you might be able to take advantage of simply by having an open mind. Forget about the big name schools. Look at some of the lesser known D1 and D2 colleges. You might be pleasantly surprised...