don't worry, it's easy (promise)
Messages on the iPhone are stored in a sqllite file inside of the backup. If you have no idea what a sqllite file is, well, then you have a little more homework to do, namely install sqllite so you can... read a sqllite file. :)
Once you have that installed, you need to grab the file within the latest subdirectory you can find inside the directory
Library/Application\ Support/MobileSync/Backup/ called
3d0d7e5fb2ce288813306e4d4636395e047a3d28. This file has your texts in it. I suggest you copy it somewhere else in case you corrupt it by mistake using sqllite. Once you have it, just run
sqllite [your backup filename] to load the data.
getting the data
The following query will retrieve the texts stored in this file, in a nice pipe-delimited format:
If there's more data you're looking for, this will tell you the columns in the table (sqllite doesn't use
The output you get should be usable in Excel or any other number of tools if you want a different backup of your texts.