Anyone know exactly where the starter is located on a 1975 Yamaha RD200 and where I can test it from?

Question

Just trying to get the motor started for the first time and when I hit the starter button it just clicks. Do I need a battery in it to start it?

Answer 1

It's located inside the left crankcase cover.
The "starter" and "generator" are one component.
Yes, you need a charged battery to use the starter.
Buy a shop manual. The time you're going to spend working on this bike, a $30 investment is worth it.
http://www.motocom.com/motorcycles/

Answer 2

With a question like this, I strongly feel that you do not belong on a motorcycle.