Scholarships.com
Create a profile, including your accomplishments in academics, atheltics, etc. Their searches also can help you choose which colleges to look at, and get matched up with scholarship opportunities. Free.

Fasweb.
Another great site, Fasweb offers a similar database search function, although it is more popular and has a lot of useful information. I can't say 'Free' enough times.

CollegeToolKit.com
This less-trafficked site has a more extensive set of resources to help students with the whole college picture. They also offer direct access to scholarship online applications. Also free, it is worth checking out.