Not sure how many people had issues with this, but it seems our webcast registration page was only showing new webcasts up to March 11th, so if you went to sign up for one more recently, you had no link with which to register... it's now fixed:
This session will explore Team Foundation Server 2008, its capabilities and how it supports collaborative development and rich application lifecycle management.
This session will provide an overview of Visual Studio Team System 2008 and will highlight new functionality across different products.
This session will explore the new testing capabilities being introduced in Visual Studio Team System in 2008.
sign up for the webcasts at http://msdn.microsoft.ca/vswebcasts