First, go to goarmy.com you will find the online application there. You won't be able to access the application until spring 2011. On the website you will find a list of schools that have ROTC from each state. Find one that is close to you and make an appointment with the ROTC Recruiting Officer. Visit with him/her and they will be able to tell you everything you want to know about the program, how to apply for scholarships and the different paths you can take to becoming an officer.
Do not go to your local recruiting office, they know very little about ROTC and will try harder to get you to enlist.
You can search around this board for information, you will get the good with the bad. The best thing you can do is visit a local college that has ROTC and ask your questions there.
Good Luck