We'll be working with Microsoft Visual Studio and the C# language.

The online materials are comprehensive, but if you want a textbook, an excellent reference is:

C# How to Program
by Harvey M. Deitel, Paul J. Dietel, Jeffrey A. Listfield, Tem R. Nieto, Cheryl H. Yaeger, Marina Zlatkina

We'll use ASP.NET for the Web Services aspects of the system.  You can learn about this through online materials, or obtain an ASP.NET book from Microsoft (not necessary, in our opinion).