There's a nice little Mac program called Playtime that will scoot through any iTunes playlist, including the full library, and tell you the total number of times you've played tracks and how much time you've spent listening to them. It's at
I just ran it on my whole library (2479 tracks). "You have played 8740 pieces for a total of 4 weeks, 0 days, 0 hours, 14 minutes, 3 seconds." Imagine!
There are probably others, but I like this one because it's uncomplicated and also free.
