Persistent Page Indicator is an article by Stephanie Sullivan at the CSS site Nemesis Project. The article shows you how to use Dreamweaver and CSS to create a “you are here” button state on the current page in a web site. Sullivan’s articles are always well written and informative.
I had some problems with the navigation at the Nemesis Project site and am hoping that the link above leads you directly to the article mentioned, but if it does not you should be able to find it under the Guest Articles menu.