Is there a practice Drivers Permit Test and/or a book to study by ?

I'm 15 and in a couple months I will be able to take the permit test. I live in virginia. Is there a book to study by on the internet ? Is there a practice test that I don't have to by ? I have a droid so I would like to have the book to where I can download it on my phone. Please help. Thank you .|||The permit test is nothing but simple road rules basics. But if you really want to, you can go online and search for practice exams. I know each state has at least one online somewhere.