Yes, MC is the best, and it's a pain that programs like RealMedia and iTunes try so hard to make sure you have their software or else certain media types won't play -- luckily they politely leave things open just enough that with their quick footwork, JRiver's MC is able to still play those file types (so long as basic QuitTime and Real software is still installed).
Of course, with a little bit of work, you can go into your system start settings to make sure Quicktime/iTunes and Real don't boot up automatically, without any major drawbacks... that way you can keep the software on your system for when you need it, without allowing it to be so invasive. And then there are free programs like QuickTime Alternative and Real Alternative that let you play those file types without installing the true versions of Quick and Real -- although I don't know if they're legal or not (probably not) -- I've had great luck with those, and they seem to work fine with MC in most cases.
For legal music files that don't have proprietary software attached (real MP3s instead of mp4, etc.), there are good alternative sites out there, although you might not find every tune you want .... for indie music, classical, opera, comedy, and some jazz, etc., I almost always use eMusic, for instance, which gives you MP3s you can keep forever (this is a monthly subscription service). And then there's the Live Music Archive, which offers free MP3s for bands that authorize bootlegging of live concerts (there's a lot more available on the site than you'd think).
And then there are those grey areas, like the Russian MP3 sites (some seem trustworthy, some are not, but none of them are strictly legal to my knowledge), which claim to be paying proper royalties to the record companies, but are selling music so cheap that it's hard to believe. Combining eMusic, the Live Archives, and one Russian site (which has millions of tracks of mainstream pop, rock, and electro/dance), I'm usually able to find everything I could ever want. And those few times I can't, I buy the actual CD
... Overall it's more convenient (better quality, tracks are well tagged and organized, you won't get arrested, etc.) than stealing music while you'll still be able to avoid DRM (and save money).
I've got a more specific rundown of all this (and much more, and a plug for JRiver's MC) here:
http://celebritycola.blogspot.com/2005/03/cheap-music-for-masses.htmlActually, one of the most fun legal (and completely free, for now) music sites I've run into this year is Pandora.com -- you can't get MP3s off of it, because it streams the music, but it's a "smart" site that quickly learns what kind of music you like and tailors the stream (instantly) to those likes. I'd love to see MC incorporate Pandora some day -- so that we can stream Pandora's music through MC, and perhaps even have it integrated with the MC star-ranking system so that our own personal collections will shuffle in-between Pandora songs or something... I'm just thinking out loud now... but it would be cool. Accuradio and Last FM are similar but I hit some bumps using those (Last FM charges a fee; Accuradio didn't always work) ... Maybe MC can work with one of these services and I just don't know it yet.... Pandora recently partnered with the Squeezebox hardware maker, so they might be open to a partnership with a company like MC....