Online marketing changes more rapidly than any one person can keep up with, yet staying current is of vital importance. One great source for current information and advice is ClickZ.
This comprehensive web site’s mission is quite simple: to help interactive marketers do their jobs better. They publish a number of informative newsletters, but what I find most useful is their “search” feature. Look for any online marketing topic and you’ll quickly have a list of brief, informative, recent articles from a number of online marketing experts. It’s one of the best places to start for a quick education on almost any subject.