If you use iTunes for your music and like going to see those musicians, then you have to install this killer ITunes add-on. It’s called iConcertCal. In their own words:
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.
What this means is you install this little piece of brilliance and it creates a calendar within iTunes (under Visualization) of upcoming concerts in your area by the musicians in your music library. Freaking awesome! And free!