It’s a common use case: you’ve got some JSON formatted data and you want to interface with it using your favourite programming language C#. You can write the appropriate classes yourself, or you could use the fabulous json2csharp helper page.
Source 1: http://json2csharp.com/
Source 2: http://jsonclassgenerator.codeplex.com/
Source 3: http://json.codeplex.com/