theres a few things you can do
if your in school, see if your college offers an 'event management' class. you;ll learn a lot.
second, you can just make it happen.
you need a venue, a date, sponsors, a company that will take on the liability factor and a way to promote.
i;d say the easiest way for you to get the ball rolling would be to start networking your way around the block and meet up with the people who set up these events, ask as many questions as you can.
For my first few events, i was lucky enough to have an internship boss guy who was super stoked on what i wanted to do, he helped me in everyway he can. I also dealt directly with the parks and recreation department to see what kind of assitance they could provide and it turned out that those crazy rednecks are good people.
your biggest problem is going to be in securing money for the prizes, as well as paying for the infrastructure of the event. Beer companies have the dough, but some venues don;t want to be assoiciated with a bunch of drunks.
hope that helps a little, good luck with the idea, it;ll be awesome if you can pull it off