A good source is old tv's if you find them. You can usually get 1-2 lbs of clean copper out of them with minimal effort. open the back, there is a cone on the back of the picture tube that is wound in copper wire and there is a degausing cable wrapped in electrical tape around the picture tube. If you feel like going a little farther you can snip all the wire and cords and throw them in a barrel they add up pretty quickley and in my area they pay .50 a lb for them. You can pull the transformers out and the scrap yards will pay for them as electric motors (about 15-20 cents a lb in my area.
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