Okay, so am building a plugin, and learning a bit of C# in the process.
I am having a hard time in finding beginners tutorials, most stuff is about people who know C++ or Java and move onto C#. Another big portion is about how to use MS Visual Studio (2005 and/or2008).
The only good tutorials I found so far are:
For beginners:
http://www.csharp-station.com/
Specific stuff:
http://www.codeproject.com/KB/cs/#C#%20Programming%20-%20Beginners
If any one else knows a decent course, we might start collecting some links and make it in a Wiki.