How can you get 3.1.3 for your iPod Touch?

Plug your iPod Touch into your computer using the USB dock connector. You then need to go to iTunes and click on your iPod Touch on the left hand side. A screen will come up displaying information about your iPod. Click ''Check for updates'' and it will automatically search for the latest firmware version for your iPod Touch. It will then automatically update for you.

Hope this helped.