I got it to work.
From "manage.windowsazure.com", click "New", click "Store", click "Bing Search API"
You should now have a "bing-search" entry in Azure>Add-ons. Click on it.
Click "Download Proxy Class", and add it to your project.
When you build your project, you'll see a bunch of compilation errors. To fix these,
1) Install "WCF Data Services Tools for Windows Store Apps" from here:
http://www.microsoft.com/en-us/download/details.aspx?id=30714
2) Adding the following references to your project:
C:\Program Files (x86)\Microsoft WCF Data Services\5.0\bin\WindowsStore\Microsoft.Data.OData.WindowsStore.dll
C:\Program Files (x86)\Microsoft WCF Data Services\5.0\bin\WindowsStore\Microsoft.Data.Services.Client.WindowsStore.dll
Back on the Azure "bing-search" dashboard, you'll see "You can use the following code to call the service.". Click on "Insert account key" in the code, AND THEN copy it to your project.
That did it for me, hope it works for you too!
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