Well I don't know of any software to make a back-up, but if you have picture messaging enabled, you can send it to your e-mail!
Just click send a pix message and put in your e-mail address, and go to the very bottom where it says name card. select it, and you can pull up a contact to send the info of(this was made to text friends contact info of others)
Anway, just select whom you wanna send the info of to your e-mail. Once it is received in your inbox, you can download it to your computer(you should be able to pull the info up in outlook). or you could just make a folder with all those files for your e-mail account(like gmail).
then if your cell is ever lost or stolen, you can just send all those texts to your new cell's "number e-mail" which for verizon(so these can be received) will be yournumber @ vzwpix.com (without spaces...my post count is under 20 so it won't emme. ;_

. You then download the attachment to your cell via the picture message!
(I've tried it and it works fine for me)
It may be tedious but at least you'll have a back up!
Also, before you send it, you may want to make the subject line the contact's name. Then you can just select the numbers you need/deem most important/can tell which ones you've already installed.
I need to actually do this(I tested it, but have yet to make a backup folder and put all my contacts in it!)