You can find seasons 1 and 2 at Yideo and buy a DVD copy on Amazon ... You can't have a list of 70s kids' shows without including the most important one: Scooby-Doo, Where Are You!
If you haven’t seen both of the theatrical live-action Scooby-Doo movies (or you haven’t seen them in a while), then don’t miss out on them before they leave Netflix at the end of the month!