There's two places you can check for sample code and reference. First is the online documentation.

http://help.infragistics.com/Help/NetAdvantage/NET/2008.2/CLR2.0/html/WinLayoutManager_Using_the_WinLayoutManager%20Components.html

Unfortunately, the documentation there isn't great, but will give you an overview of the idea behind the WinLayout Manager. The second place to check, requires that you downloaded the bundled distribution of your product. Inside that archived bundle is the installation package for the SDK. It contains the sample code that you can refer to when Infragistics doesn't document the usage with their documentation.