I'm very new to most things electronics but have a plan to learn. I'm looking for guidance in whether Arduino is the right way to go or whether there is a simpler or cheaper way.
I would like to control three unipolar (i think) motors for very basic cnc style plotting. I need it to be as cheap as physically possible (not due to budget but due to project goals). I would of course like the plotting to be accurate but understand that I would be making some rather large compromises on hardware.
Why I'm leaning to Arduino:
Driver boards are expensive and I need 3 - Arduino using motor knob seems fairly cheap?
The main board of an arduino is expensive - But I can buy one for prototyping and make my own limited one to cut down costs?
USB - I like usb - so does my macbook
What do you guys think - I ultimately want to control 3 cheap motors capable of plotting for about $30 or less (cheap as possible) - I am currently completely out of my depth but will learn whatever I need to learn to achieve my goal.
Thanks in advance
Buy an arduino - perhaps not an 'arduino' made board but there are many compatible ones which are cheaper (and many which have more features too).
As for controlling motors - depending on the current you might be able to just go for a few L293 driver chips.
mowcius - thanks for the reply - I'm really just trying to gauge my options before I set down a path!
Are you saying I could simply control the motors like this:
If so, then it would be theoretically still fairly cheap to do this:
These need 1 i/o pin each - in both scenarios - So therefore I will need:
motors - 4 x 2 = 8
limit switch = 3
and a few extra for some expansion - is that correct?
Arduino is looking more enticing, I'm getting ready to order my starter kit(s)! 
If you want really cheap, you could buy a bootloaded ATMega chip ($6 at www.gravitech.us), and these parts from dipmicro
16 MHz crystal
two 22 pF caps
two 100nF caps
one 10K resistor
and wire it up on a perfboard. That'd be a really basic arduino. I have a picture of one wired up with just the connectors I needed, will post a link to it when I get home.
Or get the serial version bare board from mouser
and build one up yourself - will need a couple dollars worth of parts (all available at dipmicro also, mouser would have the same - I don't see preprogrammed atmega chips tho) and a USB to RS232 cable for your mac to talk to it.
I bought 5 of the bare boads and parts from dipmicro to do that, haven't found time to put one together yet.
Something like that. The ULN2003 or L293 is a good place to start - there are many examples and tutorials for them around.
@yydoctt, I'm always a sucker for something cheap. I found these cool small stepper motors with driver boards which I can sell for $4 each:
http://arduino-direct.com/sunshop/index.php?l=product_detail&p=126
They are small but have a gear reduction. Maybe they could work for a really low-cost plotter...
I have some stepper information here: http://arduino-info.wikispaces.com/StepperMotors
I will be putting an example of running these motors up soon...
And I have a $17 Arduino 168 Open Source Copy (AKA Clone) here: http://arduino-direct.com/sunshop/index.php?l=product_detail&p=6
Problem is cheap shipping is slow 
Where in the world are you??? Not Brazil or Italy I hope...
Ideas, anyway....
DISCLAIMER: I mentioned stuff from my own Shop...
Guys - that is all extremely helpful information - thank you!
I am in Hong Kong so everything is very much of an issue of delivery - The project I will start when in the UK, in a few months from now - so I'll have to source everything from there or the states - as inexpensively as possible.
Mowcius - your very few words have been very helpful! I think that is indeed the cheapest route
Cross Roads - that is an excellent idea - I see this thing getting very cheap. Would you mind posting a picture as a reference for me? As for programming the chip, if I understand you correctly, the budget I have is just for the parts I will be using I don't mind spending a couple of hundred on programmers, tools, learning resources etc. So I could happily buy an arduino board to program it - plus I will be getting one very shortly to start learning!
Terry King - Thanks for the links, those motors with driver boards are insanely cheap - I have seen that driver board somewhere before - in my mass googling. To be honest, if I can make it cheaper than buying it then I will, but that does seem insanely cheap! The arduino clone is too expensive I'm afraid. I think I will go down the route Cross Roads suggested.
All of this is a few months away, so thanks very much for the information guys.
I'm going to go learn Arduino now!
Thanks
Here you go.
I have external 12V supply and off-board 5V regulator for powering LEDs, I bring 5v/Gnd over to this card from there.This card then drives Transistors on 2 cards to turn on bankds of LEDs.
Thanks for that, I'm sure it will come in handy, definitely looks like a cheaper way to get this done!
Starter kit on order
Thanks again, all the best