This may be obvious to some, but it took me a couple of days to realize.
In the new full screen Cover Flow view in iTunes 7.1, you can search by typing in the name of an artist or album directly to the full screen view, without having to minimize, and click in the search box.
Typing in a letter will go to that section of your collection; typing a few letters quickly will treat the input as a search term.
[robg adds: I couldn't make iTunes find album titles in this manner, only artists' names.]
Mac OS X Hints
http://hints.macworld.com/article.php?story=20070308163853478