Spectrum analyzer

Would someone be able to suggest the parts to look up (or provide links or books to read) to build a spectrum analyzer. I read New to Electronics F.A.Q. and still do not know what I should be looking for.

I would like to have a bunch of LEDs move to the music, powered from a wall outlet. I program in C++, Perl, Java, etc. on linux.

Thanks!

this one is *very* nice :
LED Bar Audio Spectrum Analyzer | YourITronics

thanks!

link to the source and instructions: **broken link removed**