I've come up with a good way to keep a reference to tutorials on the web.

1. Make a tinyURL (http://tinyurl.com/) to the tutorial page
2. Include the resulting number in the file name.

Taking the ArtRage cartoon tutorial as an example:-

1. I made a tinyURL for it, which gave me http://tinyurl.com/eztyr
2. Then save it as something like "ARcartoonTut_eztyr.ptg"

Then at a later date if I want to find the webpage tutorial again, I know I can find it by adding "eztyr" to the end of http://tinyUrl.com - http://tinyurl.com/eztyr