zipquick

I am trying to develop a website and my boss wants me to provide the store with zipcode locator within a week's time. I am still new to PHP and MySQL and as I go through some websites, it is not just a one week job for me to work from scratch. He is ready to shed some money on getting a script for zipcode/store locator. Can anyone suggest me which online scripts are good to buy. Or are there any good free scripts too??? Thanks Zipquick