You might not have noticed but the recently announced Visual Studio 2005 Express Beta allows for doing Web Service development.  Download the Visual Web Deveveloper 2005 Express Edition Beta and one of the types of projects you can create is a Web service project.

Here's the default C# Web service project:

using System.Web;
using System.Web.Services;
using System.Web.Services.Protocols;

[WebServiceBinding(ConformanceClaims=WsiClaims.BP10, EmitConformanceClaims = true)]
public class Service : System.Web.Services.WebService {

    [WebMethod]
    public string HelloWorld() {
        return "Hello World";
    }
   
}

You can also develop in Visual Basic or C++.

   -Matt