A dofollow site blog or forum will help to get a good pr when Google updated their page ranking. To know if the site is a dofollow or not then you can simply look at the coding and look for a “nofollow” attribute.

Just to add a bit of information where you left off at ChocoGuy, if you don't know how to view the website coding (which I know many people who do not) you simply right click with your mouse and select page source. Doing this will throw a pop up with the site coding for your viewing pleasures Hope this helps a bit and great advice ChocoGuy!