I have thousands of CDs that I've bought over the years and mangaed to rip into iTunes, 175 GB so far. I feel bad that that they're collecting dust, as I mainly listen to music via 2 60 GB iPods, one devoted to jazz, the other to non-jazz.
I've surprisingly bought several hundreds of tunes from iTunes, never thought I'd do that, but many are for my cousin (he doesn't have an internet connection). Many of my own iTune purchases are "guilty pleasure" types. I actually spent some time to go over various playlists there. I've also downloaded tv shows from itunes.
Actually, you can find some interesting things for sale online that are not avialable in the brick and mortars. For exapmple, the trumpeter Dave Douglas was selling an entire week of his live shows from his website and I bought it. It wasn't as convenient as iTunes, but I managed to download it ok. I later found out that when I imported the non-itune purchased music into iTunes, I should have re-set it to "MP3" (everything else is defaulted to "AAC or MP4"), Hopefully, the sound quality didn't suffer.
The thing about buying CDs: for many years now, I'll go buy many of them from used Record stores Who the hell wants to spend $20 for a cd when you can find it used for $7-10??
Also: I find that if I want to listen to something new and am unsure about purchasing it, I may sometimes find it at the local library, particularly European classical music, which I don't know a lot about.