Finding new music

I have a lot of music. Over 450 albums - all digital. Surprisingly, I listen to most of it on a regular basis. The number of artists that I listen to has dramatically increased making it increasingly difficult to keep up with new releases from my favorite artists. I often discover new albums months after they've been released, if at all. It's a manual process that relies heavily on random discovery and friends (thanks!).

Why isn't there is service that uses the built in meta data information on your existing collection to alert you when new albums are released by artists that you already track? For example, the program would say, "Calling the World by Rooney was released on July 27th, 2007. Click here to sample and purchase". The developer of such software could offer the service as a free download and generate revenue though affiliate programs such as Amazon and iTunes. Who knows - maybe this service already exists. Please email me if you know anything like it.