I have made my own sex toys but I used what one would call more professional materials. I weld and have made my own spreader bar. It was lovely and I plan on making more sizes. I also work with clay and have/will make toys with that.
But I hear the clothes pegs work well as nipple toys, as you said. I have also heard of using flippers like you use in cooking(buy new ones and don't use them to cook with of course) as paddles.