Out in New Jersey, Princeton area to be exact, you can find some stuff on the curb such as CRT TVs and CRT Monitors, and other bits. But the yard sales... They are a whole other thing, the yard sales are amazing! Since the people in that area are like high-to middle class they have all kinds of computers at rock bottom prices. I got my pristine Apple][e for 40$.
The next day that same guy was selling an LC3 kit, but my dad did not let me buy it