This may be obvious, but now that Inquisitor has been bought by Yahoo, the instant display of web sites matching your search terms only works if Yahoo is set as the preferred Search Engine in the Inquisitor (Search) Preferences in Safari. It's set this way by default (so Inquisitor works out of the box), but if you prefer to use Google for your searches, you'll lose the main benefit of installing Inquisitor.
Mac OS X Hints
http://hints.macworld.com/article.php?story=20081015013121143