I am frequently surprised at the quality and interestingness of the automated recommendations I receive. Admittedly, most of those are movies on Netflix rather than books, but I have found that the "people who liked X also liked Y" (described above as "simplistic") style of recommendation actually works pretty well, as do recommendation lists by people who seem to like the same things I do.

Writer, not seller, sheesh. Was reading the post above me while typing.

It's difficult to imagine a book from a seller as popular as Picoult not being available, but we take your word for it . . .