There can be many ways to get your unlock code. If your contract period is complete you can ask your cellular operator for the unlock code. But, they do make it very difficult for you to get the code. You can also visit spam edited by ddp and can see different options there to get unlock code for a price. Choose any price appropriate for you. Hope this helps
Sorry i'm not sure if your fone is in the links below But as said above by danielzar if you are on a contract your fone should "already be unlocked" if not get on to provider and ask/demand the NAC unlock code as you "should" be entitled to it, Have a read at what i said and check out the links in>>>>>HERE<<<<<