Last month I've presented a simple newbie's tutorial about NTS - Net Topology Suite.
Here you can download the code sample & presentation.

What is it NTS (Net Topology Suite)?

• implements geometry model defined in OpenGis Consortium (OGC)
• implements  simple features inside the OpenGis Consortium (OGC) as Geographic Data access
• implements Some great OGC writers as: GmlWriter (Geographic markup language), WktWriter (Well Known Text)

How do I know whether I need NTS:

1. You are coding a GIS (Geographic Information Systems) applications
2. You want to use a known Convention for Point, Polygon, Polyline etc.
3. You want simple implementation for OGC

3 times No - you don't need this
3 times Yes - you must read this article and probably use it.

You can read more about Kml & C#3.0 - at my last post.
I will keep posting more samples in the near future.