IS there a toll which will tell me whether the website I'm on has a nofollow tag on the links and whether my links are "nofollow" or not?
You can use http://www.backlinkwatch.com/. This tool shows nofollow flag for each of your inbound link.
I've used Market Samurai. Probably not as easy as those, and you have to pay for it. But it's nice when trying to decide which sites to bother with, because you know in advance if they follow or now.
There is 3 ways you can find a site is dofollow or nofollow 1. Search status plugin from firefox. Enable the highlight nofollow option to highlight nofollow links on any page you view from firefox. 2. Right click on the link and click properties. If the link properties shows external nofollow or nofollow, then it is nofollow. 3. View source of the page and search for the anchored text with link that you want to verify. If the nofollow attribute added, then it is nofollow.
NoDoFollow is the simple and best ever tool to check no follow links and I am using it for 2 years. Its easy to Install and use. Its a firefox add-on. And you can get it at https://addons.mozilla.org/en-US/firefox/addon/5687 Paul
try the program in my signature, for every link it will tell you if is nofollow, the anchor, the age of the link, the theme of the page...and much more, try it, is free