I buy classical music from
magnatune.com price is very reasonable (about 5 US$ for a CD), it is mostly indipendent artists. The quality and interest are surprisingly high.
IBS
www.internetbookshop.it/ Full price, large selection
I buy light music from
fiesta
http://www.mp3fiesta.com. Prices are so cheap that I suspect this to be highly illegal.
I some time make gifts through itunes.
I some time download from blacknet. Less and less though, practically only if I can't find it on IBS.
My bulk of music is from self converted CD's. We both had a sizable collection that we merged when we started to live together about 14 years ago. She has a huge collection of pop rock and jazz, mine is mostly classical and jazz.
She is an itune fun and has had ipods since they started. I hate that system and have used mp3. I have not loaded any music on my new touch4, yet.
Only recently I have started to use YouTube.