When Buying Travel Services on the Internet was published in 1999, it came with a "freshness guarantee":
For as long as the current edition of Buying Travel Services on the Internet continues to have significant sales, I'll post updates for changed or broken URLs on this Web site.
Buying Travel Services on the Internet is no longer being ordered by bookstores (most unsold copies have been returned to the publisher), and these pages are no longer receiving more than a trickle of visitors, so--in accordance with the terms of the update policy--the update pages are no longer being maintained. However, you can view the existing pages by clicking on the section links at left.
Buying Travel Services on the Internet