It may be too late to order in time for Christmas without paying huge express-shipping fees, but here are some books you should be able to find at your local bookstore. And they're published recently enough that your giftee may not already have them (but include a gift receipt just in case).
The Appearance of Annie van Sinderen by Katherine Howe (G.P. Putnam Books for Young Readers hardcover, 15 September 2015).
The cover makes the book seem scarier than it is. Iin fact, it's not frightening at all.
This is the story of 19-year-old Wes Auckerman, in New York City to take a summer filmmaking class. While helping a classmate shoot a séance in the East Village, he meets two young women, Annie and Maddie.
He's attracted to both of them, but is more intrigued by the mysterious Annie, who seems to hear and see things he can't.
She asks to help her find a ring she's lost, which leads him to learn more than he thought possible about the history and geography of New York.
Ana of California by Andi Teran (Penguin paperback, 30 June 2015).
I loved this modern adaptation of Anne of Green Gables, about a Mexican-American teen from East L.A. Ana has been thrown out of yet another foster home. She has one chance left before she ends
up in a group home. A brother and sister who run a farm in Central California need help for the summer; if things work out, they might let her stay on for the school year and eventually apply for emancipation.
Like Anne, Ana is imaginative, if somewhat accident-prone, but eminently likeable.
Trouble is a Friend of Mine by Stephanie Tromly (Kathy Dawson Books hardcover, 4 August 2015).
After Zoe's parents divorce, she and her mother move to a small town. They've been there only a few months, and Zoe hasn't made any friends at school, but she doesn't care because she plans to study hard so she can get into Princeton.
When Philip Digby shows up on her doorstep, Zoe's intent is to stay as far away from him as possible. But she can't help be be interested in his crazy schemes aimed at finding a local girl who has been kidnapped. It takes her a while to figure out why he's so interested, but when she does, she wants to help him, even though he's rude and takes her for granted.
This has been described as Sherlock Holmes meets Veronica Mars meets Ferris Bueller, and is, indeed, a humorous caper-style mystery.