In the CMS when you click on add a page, the screen where you select the chosen template has some descriptions on the right hand side.

I assume it is possible to add these for extra templates that I create.. could anyone help me out with whereabouts they are created?

Here's a preview of what I mean: http://sht.tl/dsdN

Nice, thanks

All of my pages are nicely labelled up now... I can get rid of the postit note which I was using as a reminder!