Don't you hate it when a headline promises you something which the author can't deliver later on? Well, I guess I'm guilty of that. Of course you can't build a robot with perler beads. But you can build something that looks like a robot. So here we go:
There are many companies that offer these pearls. One of the cheapest sources is IKEA. They sell them in boxes of thousands - opaque and translucent. The number of colors is limited though. So I buy them also on fleamarkets and on ebay.
For this project I use the big plate with the rectangular grid.
You also need a sheet of baking paper to iron the beads later on.