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Please read the license agreement that came with Mac OS X. It only allows you to install on an Apple Macintosh. If there was a method to install Mac OS X on an Intel PC like a Dell or HP, we couldn't tell you how on this board, as Terms of Use strictly prohibit potentially illegal discussion.
Furthermore, installing on a PC, you don't get the great software/hardware integration Apple has developed with its software (no other PC maker makes its own operating system), and Apple uses a different Boot ROM, that even Microsoft professes it won't have support for in Vista. Though some Virtualization solutions have managed to run the Vista betas on the new Intel Macs.
Any upgrades to Mac OS X may have further changes in drivers that the PC maker would not have anticipated, thus making any installation you try on a PC only temporarily work if at all.
Macs that can run XP start at only $600 new. And used and refurbished ones cost less. I've listed many of the possible solutions to run XP on a Mac here:
http://www.macmaps.com/macosxnative.html#WINTEL