OT - Old Power Supply Sources?

[Jason Greenwood]

Hi All,

I am making a 12v Power Supply to drive my RC Battery charger.
I'm making one like the ones detailed here:
http://www.marcee.org/Articles/PCPowerSupply.htm
http://web2.murraystate.edu/andy.batts/ps/powersupply.htm

but I need an old PC Power supply to make it. Anyone have an old, cheap 
one I can buy or know where I could source a used one? Free would be 
ideal, of course. =)

Cheers

Jason Greenwood