Hello mblanken:
The temp sensing project you are planning is an interesting side trip from Mac3 machining. If you are not already familiar with the "Arduino", give it a look. It is a microprocessor board developed in Italy, with a very "user friendly" interface, which is a subset of the computer language "C+".
Many electronics suppliers make boards and components devoted to the Arduino platform. Modern Device.com, Sparkfun.com, Adafruit.com, and Solarbotics are among the more well known companies.
Also, Arduino has a large forum with projects similar to yours. However, you must be forwarned: such things can become addictive!
Mach3 also falls into that dangerous realm.