Galactica55

Hi All, I would like to receive your help. The thing is that I am a novice developer who only worked with C/C++. I had to do a research in a topic and then discovered a stie (http://www.voip-sip-sdk.com/) with loads of sample programs. As I was going through the site I found out that the provided samples are developed with a software called Ozeki VoIP SIP SDK. Also the samples are either in C# or VB.NET. My problem is that I do not know how to work with C#. Can you help with it? How should I start, by books, tutorials, Visual Studio? If you have any other solutions please tell me. Thanks in advance.