I've started a series of VTs on YouTube on Unit Testing in C#. I'm learning as I go, so I'm no authority in this area, but perhaps some will be interested to see how it develops. I expect to eventually be testing classes used inside Unity, but at the outset it's just simple examples. I'm using MonoDevelop/Xamarin Studio for my environment. For anyone who is just starting with programming in C# I have another tutorial series on Programming Basics in C#. It does not look at programming in Unity though, just some basic Object Oriented programming concepts.