A friend of a friend of mine knows I like yarn. (Yes, that's an understatement!) She had a box of yarn goods that she donated to me. Lots of very cool retro yarn, needles, and hooks.
The box also contained some old knitting books and magazines. There were some very large how-to posters, I guess used for teaching students? Here is how to single crochet. I just love getting old yarn goodies, for FREE!