The tricky part is finding a DSDT bootloader and a DSDT file that matches your hardware. At that point all you do is make a copy of your OS install disc to a USB boot drive of some sort, install the bootloader to it...now you have an OS installer that will boot on your PC. Use that to partition and install the OS, then just install the bootloader to your boot partition and you're done.
Once you get the OS installer drive built, it barely any more work than installing OS X on a real Mac. The better bootloaders come with their own boot partition selector that comes up when you boot so you can select OS X or Windows.
That's the good part about the new Ivy Bridge setups - you don't need the DSDTs or crazy edits in Terminal anymore. It really works almost "
out of the box" (with the right Apple-compatible hardware). You make a bootable USB drive with Mountain Lion (using the app "Unibeast") and install it. Then just run "Multibeast" to get the drivers installed and it works. There may be a step or two in between, but it looks really easy.
So far, the "out of box" setups with Mountain Lion are using a quad-core i5 or i7 Ivy Bridge CPU, a Gigabyte brand Z77 motherboard (I went with the GA-Z77X-UD5H) and an nVidia GTX 5xx or 6xx GPU (I went with the 670). Since there's a BIOS, you can even overclock if you want, making one heck of a powerful machine that's as stable as any real Mac.
Check out
www.tonymacx86.com for EVERYTHING on the subject, or youtube vids to watch how easy the install is with Mountain Lion (it's only a couple extra steps with Lion)
However, for those with no building experience, I still wouldn't recommend a hackintosh. It's not a good "first build" unless it's not a primary computer and you have time to fiddle with it.