You shoul dhave a digital thermometer with a probe, with the probe right on top of the glass where the UTH is placed.

As for a thermostat, low end you can get a ZooMed 500R for $19.99 plus shipping at reptilesupply.com. It's an inexpensive on/off thermostat but works fine and reliably. I've had several of them going on my corn snake tanks for over a year.

If you want to spend more, there are Ranco or Johnson Controls on/off thermostats for around $75, and proportional thermostats start at around $109 for a herpstat.