Microsoft is giving away unlimited numbers of free ebooks on many different topics. Ebooks can be downloaded using a PowerShell script. Here are the details:
And here is the link to the PowerShell code that downloads all of these ebooks for you:
Before you run this script, make sure though that you created the folder c:\book. This is where the script places the books. Unfortunately, the script is not smart enough to create the folder, though, if it still is missing.