How do I get out of an alltel contract?

When I got my phone I was in a bit of a rush and now I regret getting into a 2 year contract. I've only had the phone for 3 weeks its nice and all but I just do not want to in a contract. So do I just go to the store and tell them I want out, maybe pay a fee and I'll be scotch free? How much do they charge? I know its a waste of money but its better than paying some 2,500 dollars over the next 2 years. I called customer service but you only speak to a machine and its really frustrating. Any help is appreciated, thanks.