After so lots of google, I got a very nice link for a Large collection of Free Microsoft eBooks including: SharePoint, Visual Studio, Windows Phone, Windows 8, Office 365, Office 2010, SQL Server 2012, Azure, and more. Here is link
another link is http://social.technet.microsoft.com/wiki/contents/articles/11608.e-book-gallery-for-microsoft-technologies.aspx
Happy Reading! JJJ