there are a few tools out there that allow you to rip a cd to either mp3, wav or aiff files. Itunes is the most popular out there. Windows media player has similar tools.
Houdini also supports mp3 files along with aiff and wav.
BTW, beware of the memory implications of loading a 4 minute song at 44.1KHz since Houdini converts everything into uncompressed 32-bit samples. Something like that is ~40 MB if I did the math correctly.