Retrieving old/deleted messages Is there any way to recover the messages that I accidentally deleted on my cellphone. I am not using Google backup or any other backup service and have never synced with any other device.
Not in any simple, user friendly way.

You're really wandering into the realm of digital forensics here, unless you can convince your carrier that it's worth their while to salvage something from their logs.

Or, y'know, ask your friendly NSA contacts ;p