Not since 2006 (last iteration of the PowerPC), Macs use Intel hardware now, same as you'll get on a PC. They are pretty, but now that its possible to run OS X on a PC (with carefully matched parts and changes to the kernel, you can build yourself a Mac clone for much, much cheaper.
Really the best way to do it is to build your own computer. It's not that difficult, and there are many, many forums to help.
If you prefer to purchase an already built computer, now is the best time to do so. The market is in a horrible (and most likely sustained tumble) slump and there are many sales out there. If you don't mind the small form factor of a netbook, I highly recommend one. I've got an Alienware laptop, a Mac Pro, and several more PCs, but find myself constantly on my MSI Wind netbook ~70% of the time. It's funny, I purchased this Wind mainly to tinker with and mod it (RAM upgrade, BIOS boost +24%, OS X, etc.) but I find myself using it for almost anything not gaming related. Easy to carry it around as well. I recommend the ASUS 1000HE, purchased one for my wife, and she loves it. Great buy for less than $400 through Amazon, battery life on it is amazing.