As told earlier, Windows Communication Foundation is the new Service Oriented programming model introduced and included in .NET 3.0 framework.
Visual Studio 2005 along with extensions of .NET 3.0 WPF/WCF, helps you create WCF Services and also WPF Applications.
Here I cover how to add a WCF Service to your Client application. I am going with the genreral steps and not specific to any binding (tcp binding/wshttpbinding/wsdualhttpbinding)
Once you have your Service ready and hosted in the machine/application/IIS, fire up your Client application
1) First, right click in your solution and you should have Add a Service Reference
2) Once you click on Add Reference, you would get a dialog box asking the Service URI and the Reference Name you would like to give for that service
3) If you are sure about the Service URI , you could complete the URI and Reference Name in the above dialog box itself, else, you could Browse for your Service by clicking on the Browse button.
So this Wizard helps you add your Service and also updates the necessary changes to app.config file and creates the WCf Proxy through which your Client application interacts with the Service.