Herpstat recommendation?

[ShamelessAardvark]

if your only going to have one clutch, get a cooler,a heat pad,a good thermostat,a few filled water bottles an a small fan to circulate the air. This is cheap and been proven time an time again. I wouldnt waste my time or money on a hovabator. This is the way i have been incubating eggs and personally have had no issues whats so ever. steady temps at 88 degrees an the water bottles do a great job of holding the temp when you need to open the cooler up to check on things.

I would love to try this, but I'm not exactly tech savy when it comes to building things like this. How do I rig up the fan? Heck, where can I even get a fan?
EDIT: Oh, and would I still need a substrate? I'm thinking of going with vermiculite with a diffuser.