Working as a Sales representative for Apple, I might be able to help. As far as I know, iTunes is pretty platform independent, so as far as Machines go you needn't get a Apple Device concerning iTunes as iTunes functions the same on Windows and Mac OSX. iTunes simply remembers while your files are located on the machine if the songs are dropped into iTunes and automatically creates a library.. (Works wonders if you have a separate folder in which you dump your music in).
If you were still thinking about an Apple device though then there are several options. Does the person in question have a proper Monitor/Keyboard and Mouse? Then you could consider the Mac Mini. It's basically the same as the cabinet of a desktop computer but with Mac OSX and the programs that come with it. They come with either 320 of 500 GB drives, and are available from 600 Euros, and will definitely go quite a long way if it's used for Music and basic stuff. While it (only) had a core 2 Duo processor, keep in mind that Macs work differently and are more efficient then Windows devices concerning use of processors. ^^;