Different stepper motors are rated at different amounts of steps. For example, we are currently looking at two different stepper motors. One has 32 steps the other has 200 steps. Using the formula 360/(# of steps) we can calculate the step angle.
Step Angle of 32 Step Stepper Motor: 11.25 degrees
Step Angle of 200 Step Stepper Motor: 1.8 degrees
Given the size of the plotter that we are building it seems that buying the 2o step stepper motor is the better choice.