How are these classifications made? Is it the audience of a book or the writing?

They're made by hook or by crook (or by the individual choice/policy of the library). Usually the book is classed according to where people are most likely to look for it (sames time and queries). For children, the librarian usually evaluates the material and chooses whether it should be for all children, or classed in YA for older children. I know several libraries that put the Goblet of Fire book in YA, because of the death at the end (and will presumably continue in that vein to the end of the series).

If I'm using song lyric references for chapter titles in a book, what is the best way to credit them? An appendix at the end.

Gar, you will be required to credit them. Probably on-page, not in an appendix. You will be required by the copyright owners, who will demand large sums of money to allow you to reprint song lyrics. (Unless the song was published before 1924.)

(I'm assuming that one sentence references are still fair use - that even under stricter copyright laws,I don't have to secure permission.)

This is so in large works, like whole books, where citing one line is practically nothing, but song lyrics are notorious for (a) being so short that citing one line is considered not fair use; and (b) requiring outrageous license fees -- which the copyright owners can set as arbitrarily as they choose. I'm told some owners set fees prohibitively high, just to make sure they don't get quotes from here to eternity.

Confused: Are we talking movie rights, or a new trilogy (re: Carey)?

Books. Time-Warner has a publishing division; their sf/f imprint is Warner Aspect.

Oh, cool! That should be a fun series!

Betsy and Nutty - thanks so much for the warning. So up to seven words (credited on the same page) is OK?

I don't think it's a hard and fast rule, Gar. It's percentages -- if the source is 100 words long, 1 word is 1%. If the source is 1 million words long, then 500 words are practically nothing.

Long story short: there is probably no way on earth to fit song lyric quotation into fair use, when you are publishing something. I can't think of a publisher in the US who would not insist on requesting permission for every singly music cite, just to be safe.

[A writer I know and trust who is published by one of the big publishers] says her publisher lets her get away with seven words of song lyrics per song without buying rights.

For the 11 year old mysteries, I'd also recommend the Trixie Belden series (11 or 12 year old protagonist), possibly out of print. I loved mystery/fantasy as a child, why can't I remember more books? Grr.

I'd also recommend the Trixie Belden series (11 or 12 year old protagonist), possibly out of print.

They're back in print now and being re-released!

I don't know about songs, but with poetry, at least, permission is definitely required. I have the only permission that I know of to use Edna St. Vincent Millay's verses and verse fragments as chapter heads (in And Then Put Out The Light). Her estate insisted on reading the MS first, and then gave permission and waived the fee.

I would imagine living lyricists are at least as strict, no?