http://vbulletin.newtek.com/showthread.php?t=26572
I used matts video tutorial.
I thought it was going to be super hard, but with the video it's pretty easy to do, and i'm really happy with it.
I was doing a project for school, and I kind of waited till about 6 hours before it was due to start rendering( it was an animation with the earth in it) and I had to make sacrafices in quality for speed. So with some testing, what took my 3ghz machine 13 minutes, took my 3ghz and 2.8ghz machines 7 minutes. And right now i'm looking for some more computers to add in, but this is an excellent tutorial if your're interested.