With you already owning a Mac this becomes tons easier. Once we know what kexts/kernel are/is needed for your PC system to run OSx86 (or OS X for the x86 PCs here) then we can apply these fixes to the Hard Drive.

First I would recommend making the hard drive in your PC an external drive that can connect to your Mac. Then I would boot up your Mac with the install DVD and install to the external drive. After this, restart into this newly installed system right from your Mac and set up user accounts, etc. Now restart to your internal Mac HD to manipulate/hack the external drive with the necessary kernel (voodoo possibly) and the necessary kexts for the chipset, video, audio, and LAN/wireless.

After you do this you can install a bootloader to the HD so a PC can boot it up. I recommend Chameleon or munky's Boot-EFI method. Then you can manipulate your drives to enable dual drives dual booting (via this dual-boot method) or single drive dual-booting using Chameleon's bootloader to allow you to select the proper system partition at bootup.

Hope this helps.

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