AT&T LG Thrive Unlocked
When the LG Thrive is released on AT&T they will probably treat it much the same way they have the Samsung Focus SGH-i917 and the Motorola Atrix MB860 and not be giving out unlock codes for these devices. That doesn’t mean you won’t be able to unlock it. You can. There’s no doubt it will be locked to AT&T so if you want to use it with another carriers sim card, you’ll have to unlock it.
Get an AT&T LG Thrive Unlock Code
To purchase an IMEI unlock code for the LG Thrive you can go to UnlockCellphoneCode.com. They have great service and support most phones and carriers. If anyone will have this code when the Thrive is released, these guys will.