We have collected the lessons from our highly rated C# School into an ebook, made many tweaks and added a chapter on C# 2.0. It is now available for you to download for free!
The book starts with the basic syntax of the language, works through object orientation and goes on to cover topics such as databases, file I/O, building Windows forms applications and multi-threading, leaving you ready to start building serious applications. It's also useful to keep around as a guide. http://www.programmersheaven.com/2/CSharpBook