If you're looking for an introduction to the Microsoft .Net Micro Framework (netmf), the first three chapters of Rob Miles and Donald Thompson's book 'Embedded Programming with the Microsoft .Net Micro Framework' have been made available on the book's website.
The first chapter runs through the origins, features and benefits of the netmf. It has a nice breakdown of the architecture stack, including the CLR and hardware abstraction layers. It is 15 pages long, and gives a nice concise overview of the netmf platform.
Rob Miles is an MVP in Microsoft embedded development. He has a small space in his site for the netmf, including an interesting but slightly out of date FAQ and a forum in which you can ask netmf questions.
Donald Thompson is an architect for Microsoft Research, and was responsible for overseeing the design and management of the software, protocols, and technology strategy for SPOT which was launched back in 2002. As such he was well qualified to write this book about the netmf, which developed out of the SPOT project.