you can't. you can try ebay. they have like unlock codes for like $4 and if you want to get the blackberry unlocked you might also have to get it unlocked at the store you bought it from or from the service provider it say on the phone
hi there are many online sites found nowadays that provide the unlock codes at free of cost but they provide the codes for only older mobile models .you can get the codes from here theunlockarena here they ask the country and the provider to which the mobile is locked finally the imei number of the mobile .then they will send the codes to unlock the mobile.