Hi guys! Please help me with unlocking Sony Ericcson Xperia!

I bought mobile phone Sony Ericcson Xperia Arc, and if i put my sim card in it says: SIM network unlock PIN, and im using UK-s sim card called “Three Mobile”
Could anyone know an program how to crack it or unlock code, or program whats gives me that unlock code, and i really dont want to pay for it, so please help me, i really apprichiate that!!! THANKS!!!!
Answer #1
Hm i think you need to back mobile to provider, they can help you.
Answer #2
Shadowic replied: Hm i think you need to back mobile to provider, they can help you.
I bought phone from ebay, he sayd mobile was unlocked but it wasnt
Answer #3
Did you even try Googling?
https://www.google.com/search?q=unlock+xperia+arc
Answer #4
-paroxysM^ replied: Did you even try Googling?
https://www.google.com/search?q=unlock+xperia+arc
Yes i tried, no match for me, have to pay everything
Answer #5
call your company and tell them your going to a different country and want it unlocked so you can use a pre paid sim card while your there…trust me they have the codes you will NEVER find them on google