What's your temperature range? Thermistors are easier to work with than thermocouples, but don't have nearly the range a thermocouple does.
To measure the temperature of a thermocouple you need the thermocouple, a low noise instrumentation op amp to boost that voltage to a readable level, and a thermistor on the reading side for 'cold junction' calibration as thermocouple produce a relational voltage not an absolute one based on temperature.
Building one from scratch is not excessively easy. An MCU is a good option as most have ADC's and some have internal temperature sensors, so all you would need is the instrumentation amp and to set it within your useable range. Many multimeters have thermocouple inputs, and if you look around you may be able to find one that can read a thermocouple and has an RS232 output to hook up to a computer or MCU which takes all the hastle of building the thermocouple module yourself out of the picture.