iConcertCal is a free iTunes plug-in that monitors your music library and generates a personalized calendar of upcoming concerts in your city. It is available for both Windows and Mac OS X and supports worldwide searches.

iCC makes your digital music a concert-going reality. iCC combs websites like Tourfilter and JamBase for show dates, but saves you time by automatically matching them against your iTunes artists, then marks them on a custom, in-program calendar. In addition to updating weekly, iCC provides links for venues/tickets.