From what used/junk equipment can I salvage solenoids from?
Cash Registers use solenoids to latch the drawer in place. Sprinklers use solenoids. As do cars for multiple parts, from door locks to fluid systems. You are most likely to find solenoids at a Junk yard than you are at a electronics recycling plant or a thrift store. Consumer electronics just don't need short range solenoids, at best they use motors.