How to make eyes for knitted toys
The eyes in this one are knotted yarn...on an OWL! It's not what you're asking about but I thought you might like to see.
A toy pattern. The quote below is from way down at the bottom.
Make eyes by cutting two pairs of circles out of felt: a white circle about the size of a dime, and a black circle which is slightly smaller. Cut a narrow wedge from the black circle to make a "Pac-Man" shape. Using photo for reference, glue or sew the black and white circles together, then glue or sew the eyes to the nautiloid's face.
Hmmm, I'm afraid the links won't be much help but maybe they'll be something you'd like to know.