Hi, 

I looked through the posted, wish and unposted lists and nothing rang a bell.  This is the information I remember:

Shape:  Square (instead of the usual oblong)

Color:  Yellow

Title:  I think it was something really goofy, like Lopsy Popsy Fiddle and Gee

Subject:  The main element I recall were a variety of weird cartoon characters with huge, elongated noses

Publisher:  Scholastic Book Services

If anyone can help with the title, I will be most grateful.  :)

Thankyou,

Mark