CNC electronics

I'm in the process of building a CNC machine right now and would like a little help from the experience ones.  Right now I have $250 saved up and counting.  I'm trying to figure out what to do about stepper motors, power supply, and motor controller.  I didn't know if it be best to just buy a package that have it all in one and what would you recommend.

I'm thinking about building tinhead stepper driver if can't find a good deal or not.  I also have several desktop computers laying around so wondering if I could use the power supply from it somehow to power it all.  Then that would just leave me with buying some stepper motors. 

I'm planning on cutting wood, plexiglass, and aluminum with it.  I know I just have to work on getting a good router for some of those things so that will just have to be last in line.

 

Thanks everyone!

First question,

I hope you are planning on making a very sturdy mill, such as metal structure. Tinhead’s current mill isn’t likely stable enough for metal cutting. I have enough hardware laying around here and have had a slightly functioning cnc mill that was powered by a PSU. The stepper motors came from mpja. The driver I bought came from HobbyCNC. The board is nice and fairly easy to assemble. My issue is with the guy that makes the board rules the mailing list with a bit too much of an iron fist in my opinion. I would imagine the cheapest driver you can see constructed is here. It is a link to an instructables page that is part 2 of a set of 2 from building a mill to building and utilizing the drivers for the mill.