I'm not being funny, but if your friend has done it maybe they would be a good person to ask how 🙄 It'd probably be easier for them to explain it to u over the phone or something rather than someone here have to write out how to edit resource files.
check out www.resexcellence.com for ways to skin itunes. i am not a huge fan of most of the skins they have, but at least they have them. you will need to be able to boot into 9 and use res edit for any of the skins, but that is worth it if you really want your itunes to look different. don't forget to make all your changes to a duplicate of itunes!