These work good and don't break the bank.

http://www.bigappleherp.com/BAH-1000-Thermostat

If you want to save a little money on that unit try going to a pet store around you that sells reptiles. The model linked above is pretty common but made by different companies. Thermostats can get very expensive and with only one snake in a tank i wouldn't suggest spending over $100 on anything proportional.

Now as for use they are all pretty straight forward just plug the lamp and UTH into the thermostat and put the probe where you want the hot spot and your done. Keep an eye on the temps and adjust the thermostat accordingly. Even the best thermostats are off a few degrees here and there.