Check out this blog post by Carlie Webber at Librarilly Blonde.
She's talking specifically about email RA--like when people ask their colleagues on a listserv for help with finding books for a patron, or when we get requests via services such our email reference. But the post also serves as a quick reminder of the types of questions we should be asking our walk-in or phone-in patrons when they need recommendations.
What are your favorite "fishing" questions that you use to find out more about the patron, or the patron's children, to help zone in on the books they might like? What bugs you about reader's advisory? What do you love about it?