Here’s a great way to learn more about SQL Server, Azure, Windows Server and other Microsoft technologies with this collection of Free ebooks:

UPDATE:  Here’s a more recent list of free books from Microsoft:

http://blogs.msdn.com/b/mssmallbiz/archive/2012/07/30/another-large-collection-of-free-microsoft-ebooks-and-resource-kits-for-you-including-sharepoint-2013-office-2013-office-365-duet-2-0-azure-cloud-windows-phone-lync-dynamics-crm-and-more.aspx?wa=wsignin1.0

Here’s an older list:

http://blogs.msdn.com/b/mssmallbiz/archive/2012/07/27/large-collection-of-free-microsoft-ebooks-for-you-including-sharepoint-visual-studio-windows-phone-windows-8-office-365-office-2010-sql-server-2012-azure-and-more.aspx

Enjoy!