Hi ak47,
OS X is strictly for PPC arquitecture. It won't run on Intel based PCs.
Unless you have a PowerPC machine, you won't be able to run it.
If you do get a PowerPC machine, then I suggest you install YellowDog Linux (
http://www.yellowdoglinux.com/ ), and then install OS X. This way, you can run Linux AND OS X
simultaneously, using MOL (Mac On Linux ).
The closest thing to OS X on Intel is Darwin for i386. But you won't have the graphical user interface (AQUA). The best you'll be able to do is X11 GUI on it.
Plus it's VERY buggy (core dumps everywhere!, I tried it.)
-kwag