Click "Add", then "Feed" and enter the URL of the web site you want to track, Netvibes will usually reveal and allow hidden feeds.
If no RSS feeds available, there are many online services that converts any web page to an RSS feed on the fly.
- feed43.com offers the ability to examine and extract posts from many sites and create an RSS feed from them.
- feedity.com is a service that create a feed for any webpage.
- createfeed.fivefilters.org to create an RSS feed for a web page which does not offer its own