The day after French designer Isabel Marant unveiled her Fall/Winter 2009 collection in Paris in March, the Web sites for boutiques across the U.S. were flooded with emails about studded ankle-high boots, asking when they would be arriving and whether they could be ordered in advance.

Monika Beurmann, a 35-year-old IT consultant from Chicago, says that while looking at the fashion show on Style.com, she "fell in love with the futuristic design of the heel," and pr e-ordered...