Rubbersoul,
I have my iPod classic 30 gb hooked up to my 990 using the video 5 input on the front with a cable from the iPod headphone out to the RCA inputs. If you just want to play your music, try it out. The cable is available almost anywhere and despite what all the "audiophiles" out there say, it sounds pretty good. Just remember that the output of your iPod will affect the sound level. DYNEX makes a cheap dock to keep your iPod charged and allow you to input to the 990. As far as convenience you can't beat it. Your iPod is still portable and your music is still able to play through your system for about $10. I put all of my music into iTunes and I could use my laptop as a music server but it is not as easy as the iPod. I have a large collection of music from the last 40 years and I cannot tell a difference between the compression formats. A lot of music which was recorded prior to the MP3 format coming out is badly compressed anyway. If you import you cds into iTunes and play them through you system I think you will be pretty satisfied.