Here, in Edmonton, we have a computer & electronics recycling depot. They will gladly accept any old system from a person, and if you happen to have a large volume, they will pay you (by weight or piece, I am not sure).

I am somewhat positive all provinces and states have something similar.
California offers: http://www.crc.org/

Just G00G "recycle computers" & "Edmonton" (your city/province/state) and bingo - you should be presented with many solutions.