to control tangential cutter w/oscillating

[avengine]

Base on the mach3 manual, I know that it can control the "C" axis for
the tangential head to make the turn follow the cut line.
Now I need to know about the parts that I need to control all the step
motor.
This is what I plan to do, from Campbell Designs buy Combo break-out
board. $245
from GeckoDrive.com buy the G201 or G210, but I don't find info about
what is the different between G201 & G210, now that I have 2 motors on
X axis, one motor in Y axis and one motor in Z asix, plus one in the
tangential cutter, which one should I buy. Should I buy 1 for each
axis that is $148 x 5
on the X-axis there are one motor on right and one on left, how do the
hardware and software to control this 2 motors in sync.
on the tangential cutter it also has the oscillating, I think the combo card need to send out a voltage to control the frequency, is this availble is the combo card?
and the last thing is power supply, is there some good place to get
one too?
Did I miss anything? I find it is fun to design something to move.
any suggestion is welcome.