I did a little research and it appears that extracting the icons is not as trivial as it might seem. I've prepared a small sample that populates RadTreeView with nodes and each node has an icon of a folder that comes nativly from Windows. I read several articles to understand how to retrieve for example the icon for a folder or a hard drive. Then, having the icon (System.Drawing.Icon object) I had to convert it to a BitmapImage so that the Image control in WPF understands it. I am attaching my sample project and I hope it will help you accomplish your scenario. Additionally, please have a look at these articles for further information:
WPF - Assigning Icon to Image control
Need Working Example of Shell32's ExtractAssociatedIcon Function in .NET
Retrieving shell icons
How do I fetch the folder icon on Windows 7 using Shell32.SHGetFileInfo
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