It happens all the damn time: you're listening to a great song on the radio that you've never heard before and you miss the artist/title. Damn ADD. If this ever happens to you, there's Yes.com to save the day..
Just enter in the call letters or zip code and the site will give you a list of the latest spins for your favorite radio stations -- in real-time. You can even scroll back to the last 24 hours.
And if you really like the song, you have a direct link to purchase it on iTunes.