Hi there! A dimmer switch is the minimum control needed before you plug in your UTH, and a lamp dimmer from lowes is about $9. You will find after using the dimmer for a few weeks, that you don't enjoy adjusting the switch constantly, due to room temperature flux. A ranco off ebay is $50 (not-wired) and about 70 wired. Wired just means it is ready to plug a UTH into and plug into the wall, unwired means you need to wire it to an extension cord (there are instructions online available if you are up to the challenge)

Read this http://www.reptilebasics.com/Thermostat-FAQ-sp-10.html and you will understand the difference between thermostats (which adjust the temp for you) Then check out their prices on thermostats, I believe their prewired rancos are $70.

As for putting something IN your tank between the UTH and your bp - newspaper or any other substrate acceptable is all that is needed, even if you put a thick layer of substrate in to help reduce the heat on your bp's belly - he will burrow beneath it to the hot spot.