Anyone who builds their own water blocks, where do you find your copper? I have built some in the past using very thin gauge sheet metal but I am not satisfied with them. They tend to bend and not form a good seat on the processor.
i know that there is a "metal supermarket" near where i live. my mother picked up metal there when she did her mech. eng. technologist certification. i would imagine that there are similar small shops wherever you go, if you page through the phone book.