A book, set for release next October, is entitled Preppy: Cultivating Ivy Style, but the cover photo suggests that the book is a guide neither to ivy style nor to preppy style, but rather to a silly club kid sort of look, throwing together miscellaneous retro items so as to be slightly shocking or annoying. The individual items may be preppy, but the overall effect is not preppy. It comes closer to something resembling thrift store chic, so called. But to judge from what I have seen in the blogosphere, there are those who would characterize the look as preppy.
There is discussion of the upcoming book at Ivy Style.