Hi, Cuemaker
How many wires are there on the stepper motor's, if it's 5, 6 or 8 then there unipolar stepper's.
There are many ways to drive them, The NTE 2013 is a Darlington array chip, I guess there must be 2 of them to drive your stepper's which would require 12 output's from your computer, I don't believe that Mach 3 has a driver for that (I may be wrong about that though). Anyway if that is the case then it will up all your output's for your one printer port.
You can use 3 UCN5804B chips about 5.00-7.00 $ each or buy a 3 axis board for 100.00 - 150.00 $, This will put you into Step and Dir. Control, 6 output's used. some of those board's will allow other features such as Input's and output's.
Hope this helps Chip