its my friends birhtday soon shes gonna be 17 and i want to get her a book but shes already read all the ones i've read. so now i can't choose one and know for certain it will be good . any ideas?
That's a good idea. Better still, make her a voucher that entitles her to a trip to, say, Borders, with you, and that includes coffee and a snack and a book to the value of x amount.
That way she gets something she wants and you both get a fun birthday treat.