I finished up my first Web service today using Visual Studio 2005 and C#. As I do whenever I start with a technology that’s new to me, I turned to the Web to try to find a good example. After quite a bit of searching, I found this article to be a great starting point. It makes the basic concepts easy to follow, gives simple sample code that can easily be modified to build what you want your Web Service to do, and also shows you how you can test your Web Service easily.
Thanks Shiv Pal Singh, whereever you are!
One note: the WSDL and CSC commands are only necessary if you want to build your Web Service outside of Visual Studio, as Shiv points out.