I love this vintage bookmark I found for sale on eBay recently. Great graphics and words by Hardie Gramatky for the Children's Book Council (of America).
I did not buy the bookmark (outside of my budget) but I have enjoyed collecting it virtually, here and in my Mark My Place Pinterest page.
If you want to see more bookmarks featuring care for books, there are wonderful ones on the International Friends of Bookmarks Care of Books Gallery.