Unlock 6610 by Cable

I have a 6610 that I screwed up by entering the unlock codes too many times incorrectly -- I am not that tech savvy. Can someone tell me what the best solution would be to unlock this phone? I am heading to Europe soon and would like to swap services to a provider over there. Can I unlock the 6610 with a cable, if so what kind? If not, would I need to purchase a box? That seems a bit overkill for one use. Are there services that unlock the phone for you for a fee so that I don't have to purchase hardware?