I'm looking for a building toy, I think it may have been an Avon toy.

Red and blue plastic squares with flanges on the edges. White square pegs with grooves on all four sides. The pegs are used to join the squares by sliding the square into a groove. I think there were wheels, too.

Thanks!

Tog'l blocks?
TOG'L Sets

Thanks for your reply. Tog' block are cubes. The ones I'm talking about were flat square tiles.

Hmmm... this probably isn't it either, but I'm just throwing it out...
Lok-a-bloks

Thanks for the response. They look like fun, but they're not it. These were flat, maybe 1/8 inch thick and 1 inch square.