I agree completeltly with agentq16, I pitch using his philosophy except I have several pitches but they are all from fastball motion!! I have a simple compact motion with almost no arm movement until i have started my stride. As for pitches I throw I am 15 lefty 6-1 180 and I throw  
4 seam Between 68-74 
2 Seam about the same maybe 1 or 2 mph slower  
Cutter which is really just a reversed 2 seam grip 65-68 
3 Different variations on a circle change: 
1. Breaks straight down but not very sharp, more like a big loopy curve 50-55 
2. Regular circle change breaks down and in on rightys 55-58 
3. Breaks straight sideways, good on leftys 58-60 
 
Of those three i throw mostly number two which is my out pitch the other two are trick pitches.