Hi Scott, this is the tutorial that I used to start with.
http://gregers.fr.yuku.com/topic/11537/Prop-blur-tutorial-Picture-heavy#.VVx5E9so8XA
However, once done, I wasn't really convinced with the look of the full disc, so using the template as a basic guide, just cut the clear sections out. The yellow tips were done with a disc cut to a slightly smaller size and used as a mask.
A couple of thing I' do differently. I used .25mm clear card for the props and think going a bit thinner might be better, at least in 1\72. That, or maybe thinning the edges slightly.
On a lot of pics, there's a definite pattern to the prop in the blur, which with a bit more
airbrush practice should be achievable, along with fading the yellow tips a little towards the ends.
I hope that helps. I was surprised how easy it was, to be honest, and if I can do it, I reckon most people here can. Just give it a go
Cheers, Neil