That site also has the cheapest emergency stop switch I can find:

http://www.tlc-direct.co.uk/Main_Ind...ons/index.html

I mounted my stepper drivers in the computer case CD drive bays so it's nice and compact. If you didn't have the computer in there you could get the transformer in too, and good cooling as long as you make sure the fans don't suck in all the dust.

Old photo, before I used the right wire, but you get the idea:

Click image for larger version. 

Name:	DSC04079_small.jpg 
Views:	363 
Size:	497.0 KB 
ID:	4444

Not saying that's the best way to do it... but it's convenient and cheap. They're mounted on 1" aluminium angle.