Chappel University has launched a new webcast to give a nice overview of wireshark features. For those who didn't attend it last time(like me!) its time now.
This is the starter class to get your feet wet with
Wireshark - learn where and how to tap into network
traffic, the two types of filters used to focus on network
traffic, the basic layout of the Wireshark configuration,
How Wireshark does what it does - dissectors, engine
and graphing. Laura works with Wireshark to show
you how to quickly spot network problems using
Wireshark's Expert Info Composite and specific Time
Column settings. Get up to speed fast on Wireshark's
capabilities and begin troubleshooting and
optimizing your networks today!
http://www.chappellseminars.com/s-wireshark101.html