I didn’t used to care, but now that Apple has me in it’s firm grip once again, I love iTunes. Hell, even my friend’s band has one of their half-dozen albums available there (check it out, if you like- it’s The Fenians, a best-of album).
Make it easier for me to buy your music- it’s always the right business decision.
They’re better known by reputation amongst fans than for overall output - aside from some shorter releases they only have 4 full-length albums. They’re a modern progressive heavy rock band, heavily influenced by King Crimson among others, and have pretty complex structures to their songs.
Kid Rock’s inclusion is one early album (none of his later work), and I think a song here and there off a soundtrack or a ‘various artists’ album.
As Telemark expalined, all of Zappa’s official albums have been pulled from iTunes. The stuff that remains is the “Beat the Boots” series, which is apparently still controlled by Rhino and/or Warners, a few live “iTunes exclusive” tracks, and various cover albums of Zappa material.