Here's a post summarizing how ASP.NET Themes work.
See: Ch.9/L.2.

Here's a quick summary of what you need to know about ASP.NET 2.0's MasterPage architecture.
See: Ch.9/L.1

A short post on how to make static connections between WebParts.
See: Ch.9/L.3.

Hopefully everything you'll ever need to know about Globalization/Localization in ASP.NET.
See: Ch.10/L.1.

Here's a crashcourse in website authentication, and authorization -- including roles.
See: Ch.11/L.2.

Not a long post/article, but a short & relevent post.
See: Ch.11/L.2.

A short post demontrating how to use the DeviceSpecific syntax in order to different renderings based on filters.
See: Ch.12/L.1.

A short post demonstrating how to add custom PerformanceCounters of your choosing to your software, so that SysAdmin's can monitor your software with PerfMon.
See Ch.13/L.2

You can add performance counters to your applications -- but it assumes you know how to use PerfMon effectively in order to analyse the results.
This is tutorial on PerfMon only (putting Custom PerformanceCounters into your software is a different article).
See: Ch.13/L.2.