I'm making my own tubs and I had a few questions...

[Kaorte]

how much to thermostat and dimmers cost? Can i find them at places like wal-mart?

You can find a dimmer at the home depot:
http://www.homedepot.com/webapp/wcs/...10000003+90401
And here is a thermostat that should suit your needs:
http://www.reptilesupply.com/product.php?products_id=75
It isn't a fancy one and will take some time to get the temps right. Make sure you get your tub setup correct before you put the snakes in.