Hi,
I havn't seen many MP3 players that incorporate images. I have one but it is geared more for bands to demo original music and display thier own custom album covers. It would not be difficult to achieve on a smaller scale. In the same manner you load the external MP3 files, load corresponding images. It would probably be easiest to organize using arrays. Maybe something like...
code:
mySounds=["Sound1","Sound2","Sound3"];
myImages=["Image1","Image2","Image3"];
mySound=new Sound(this);
mySound.loadSound(mySounds[0]+".mp3",true);
myImageHolderMC.loadMovie(myImages[0]);