Interestingly I was just posting about the jazzy spies/ race car number counting skits yesterday and remarked about how someone said in one of the threads that ebay sometimes has a book from 1970 "The Sesame Street book of numbers" that has illustrations of every one of these skits. Now I'm not sure offhandedly if that was the first book, but seeing as how SS debuted in the fall of 1969 it seems like a good possibility.