I am brand new to electronics.

A guy is putting together a CNC Foam Cutter for me. He is wiring the CNC kit that controls the stepper motors and also the temperature board that controls the wire.

Originally, I was to come up with a 240watt power supply. After some discussions back and forth he has agreed to build in some components at his end -- full bridge rectifier, capactors, etc. I believe that his equipment will multiple the supplied current by a factor of 1.414.

I have to come up with a transformer - AC current in and output between 18-20volt, 6-8amp. I need to put this into a project box, fuse, switch.

How would I go about find a transformer that meets these requirements?

I would appreciate an online link or some guidance.
I live in Ontario, Canada. I assume that this transformer would be heavy and would have a high shipping cost

 

First thing that comes to mind is a old automotive battery charger, I'm not sure the voltage will be as high as you specify.

 

Check out Marlin P. Jones & Associates' offerrings:
http://www.mpja.com/powersupply.asp
You can purchase a complete supply for less than it would cost you for a transformer.

Switching supplies will be much less expensive and much more efficient than traditional linear supplies.

But if you really just want a transformer, this one would do it for you:
http://www.mpja.com/prodinfo.asp?number=7846+TR

 

I believe that's the cheapest I've ever seen for one of that size !

 

I ended up going with a Hammond. In turns out that Hammond mfg is only about 1 hour drive from my place. I actually bought from a small electronic store that is around the corner from the factory.