Nokia 3100 Free Unlocking Suggestion

Hi..Friends help me in unlocking Nokia 3100 Model mobile from T-Mobile network US.My nokia 3100 locked to t-mobile us.I Found the free unlocking code in the site unlock-free.com i want the Unlocking suggestion which is the best whether unlocking code? or Unlocking software?I think code is best to unlock the Mobile.

As this is a nice mobile & i am using this mobile to.Recently only i unlocked this mobile from the site named Mobile Unlock Solutions - The Ultimate Website For Mobile Phone Unlocking