if you are looking to unlock your xperia ion at&t and other networks then you can do so by code. here is a thread where you have a chance to grab a few free codes. http://forum.xda-developers.com/showthread.php?t=2079966 Check that thread on xda also take a look at www.htccode.com. Enter your IMEI no and you will get the code.
Just now i had unlock my xperia ion lt28at. very cheap just USD11.80 using AT&T USA Slow Unlocking Service.They said it will complete within 2-3 day. In my case just 1 day only.Good service check it at http://www.superunlockcodes.com this is the cheapest that i know..
