The easiest way to find all new messages in forums that you want to follow is to use the Global Newest configuration page and then bookmark the resultant page, which will show the most recent posts in chronological order. If you use that bookmarked page while logged in, posts that you haven't read will be noted as "new".

All of the forums are viewable in several ways which you can configure. Try the "switch views" and "latest messages" buttons at the bottom of message listings. Logged in users can also change some settings through their "My Control Center" link.