I don't understand what's absolutely so amazing about iTunes. However there's no Linux version as TB0ne
very well said. You might be able to get it to work to some degree under wine
, but don't count on getting it to work 100%, or in an easy way. Search their database there (there's a text box for that on the bottom left of the page) for iTunes and see what you can get. Search also the forums for your distro because there might be howto's by other users or something.
I don't use iTunes so I can't be sure to what degree it can or cannot work.
However, I'd start looking for alternative like Amarok if you really want to use Linux. Either that or complain to Apple.