Use the following resources for training your organization's business users and/or Information workers on SharePoint and SharePoint Designer. Note that these are not the hard-core developer training resources but these can be a good start for a developer to start learning about the general concepts of SharePoint and how to perform certain tasks in SharePoint.
The very first resource is the training that comes in two flavors; the Standalone Edition, which can be installed directly on the end user's machine and the Portal Edition which can be installed on a common MOSS site which is accessible by all of the end users.
Office SharePoint Server 2007 Training (Standalone Edition)
Office SharePoint Server 2007 Training (Portal Edition)
Office SharePoint Designer 2007 Training (Standalone Edition)
Office SharePoint Designer 2007 Training (Portal Edition)
Apart from the above training, check out the training for more advanced business users @ SharePoint Designer 2007 Business Administrator Training and the Six-Part Series for getting the most out of the SharePoint Designer.
Road maps
Since WSS/SharePoint is huge and has so many areas for one to learn, hence it would be good to have some kind of guided learning approach (or focused training) where one particular area of SharePoint is targeted, learned and explored in detail and then move on to the next area.
Microsoft has done a good job coming up with the road maps for such training. Following are some of the road maps that I found; there could be more, but I am not sure.
Roadmap to using SharePoint Server 2007
Roadmap for creating and managing sites
Roadmap for creating and configuring libraries
Roadmap for creating and customizing Web Part Pages
Roadmap for giving users access to sites and site content
Roadmap for managing navigation
The following articles provide some of the important concepts and training that a power user should have or better yet have your end users go through the training material located @ Help for SharePoint Server 2007
Understand groups and permissions on a site
Enable anonymous access
Give users access to a site
Manage permission levels
Introduction to sites, workspaces, and pages
Manage sites and site collections
Work with site content and structure