Thanks for writing.
The Telerik RadControls app should be available for all marketplaces. Could you please try searching for items with the keyword "Telerik" and see whether you get the expected results?
As for the source code of our Demos app, it is provided in the RadControls for Windows Phone 7 package that should be available for download from your account.
I hope this helps.
All the best,
the Telerik team
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