Here's a website, Purple Kitty, that is restoring vintage crochet patterns. (They also have a sale going on, I have ordered from them and they do have fast service.*)
Their crocheted butterflies patterns are available as a downloda ($2.49) or for free at their website:
I have never seen the book that the butterflies come from (there's a photo of it on the website) but it looks pretty cool.
Here's a freebie for you - the Interweave "Crochet" magazine.* Yes, it is a subscription form. But the first issue is yours to keep, you can cancel the subscription after that one. I decided to subscribe instead of trying to track it down in my area. It saves on time and gas. You can check it out here:
*no kickback received - you know the joke, I'd take it if they offered it