Actually, good on ya for thinking ahead. Your chances of getting in to an awesome school just went up...
In college, involvement is an important thing. But be careful, if you just sign up for every club in the world and attend a few things here and there you may end of with a well padded but content-less resume.
Try to get community service, university service, and some other academic organization involvement. Try to be the lead organizer/president as much as you can.
As far as recommendations go I think getting an "awesome" person to do it generally a bad idea. Everybody knows a federal judge. Just try to find two professors who you really do enjoy class from. Get to know them, ask about undergraduate TA opportunities. You want two letters from professors that know you academically and personally. You want the letters to reflect your good nature, intellect, and people skills. They don't have to be famous people, just people who know you.
As for a third or fourth letter, you can get creative and use someone who is linked to a strong aspect of your resume (maybe the chairman of the board at a service organization you volunteered at for 200hrs...)