Visualization....

This is more of a research question, ....

I have in mind to create my own visualizations ...like the ones they have for Windows Media Player, ....but not for windows Media player !

what woudl be the best approch to create an application (for windows) that would take a certain audio play back and produce graphical effects accordingly...like an equalizer ...

can someone point me in the right direction?
has anyone done anything like this before?

what is the best way to listen to the music and bass and etc and adjust the graphical out put accordingly ?

any articles/links/code would be greatly appriciated.

Thanks