The briskly written and often amusing Web Digest for Marketers is an annotated listing and review of Web sites with particular utility for marketing, promoting and selling. On the other hand, if editors Larry Chase and Roberta Kane decide a site is interesting or simply entertaining ("Don't click here if you have a life"), it's in. WDFM is a service of the Online Ad Agency, which also provides a number of online essays on marketing, advertising and how to make proper and effective commercial use of the Web. E-mail:;