This is an AWESOME resource. So much so that I capitalized, bolded, italicized, AND underlined AWESOME. I just found a page on Technet with TONS of Visio diagrams for every type of SharePoint Deployment/Topology/Project.
Head on over here: http://technet.microsoft.com/en-us/office/bb310619.aspx and scroll down to where the product says "SharePoint Server 2007"
Some of my favorites include (and there are many more on the site):
SharePoint Server Application Security
Download this reference to learn about basic principles of SharePoint Server security, default groups, site-, list-, and item-level permissions, and more.
SharePoint Server 2007
SharePoint Server Backup and Restore
Download this reference to learn about supported types of backups, backup and restore tasks, content recovery, and more.
SharePoint Server Topologies
Download this reference to learn about topology design principles, example topology implementations, and more.
SharePoint Server Baseline Site Hierarchies
Download this reference for example site hierarchies.
SharePoint Server Customization
The purpose of this model is to showcase the top SharePoint Server 2007 customization areas and what features a user can modify to meet their objectives.
SharePoint Server Database Administration
Download this reference to learn about database administration in SharePoint Server.
SharePoint Server Enterprise Content Management
This poster presents the features in SharePoint Server 2007 that support enterprise content management, introduces the predefined content management sites, and illustrates how content moves from one site to another.
SharePoint Server Extranet Topologies
Download this reference to learn about perimeter in proxy, back-to-back perimeter, and more extranet topologies.
SharePoint Server Inter-Farm Shared Services
Shared Service Providers can be configured to provide services to multiple SharePoint Server 2007 farms.
SharePoint Server Search Administration
Download this reference for the search administration process, search topology, and more.
SharePoint Server Shared Services
Learn about shared services, provider architecture, recommended topologies, and more.