Vivarium Electronics VE-200 and http://www.reptilebasics.com/thermostats and Herpstat http://www.spyderrobotics.com/store/

Keep in mind that a reliable thermostat is the single most important thing when it comes to husbandry. Yes there are cheaper thermostat however they often fluctuate, break down and need to be replaced.

Best thing you can do is invest in a good thermostat it will be worth it in the long run.