Data sources tab is missing in visual studio 2010

I started reading the Pro Business Applications with Silverlight 4 and I'm having the following problem here with my visual studio 2010

I can't find the data sources tab page as mentioned here:

When you open the Data Sources window in Visual Studio, you will find that a data source has already been created for each domain context created by RIA Services in the Silverlight project, with the entities that they expose beneath them (as shown in Figure 6-2). Dragging and dropping one of these onto your design surface will create both a DomainDataSource control and a bound control to display the data.

I know that the Data Sources window and Data menu are intentionally disabled in Websites and Web Application Projects but my project is a Silverlight business application.

Can someone tell where i can find this window or what should i do to create the DomainDataSource control and the bound control?

Thanks!

If you have MainWindow.xaml open, the DataSources tab is normally right next to the Toolbox tab.

If it does not appear there, go to View -> Toolbars, and turn on the Data Design toolbar. Click the Show Data Sources button.

Or just use Shift + Alt + D