This 2003 handbook to cataloging discusses the basics of using information from books and other media to create appropriate metadata for catalog listings. Read has a sense of humor about the practice and this may be an enjoyable skim for librarians and patrons alike.
One aspect worth mentioning is a point with which I disagree; when discussing children's literature, she suggests that for material that some families might potentially find offensive, that a note to that potential should be made in the record or the sticker affixed to the cover (p. 212). I do not agree because, of course, "offensive" is subjective and making such notations can serve to divide and alienate marginalized populations.