Some excellent free resources (ebooks).
Free eBook: Understanding Microsoft Virtualization Solutions (Second Edition) (6 chapters by Mitch Tulloch)
Free eBook: First Look Microsoft Office 2010 (14 chapters by Katherine Murray)
Free eBook: Windows 7 troubleshooting tips (short eBook by Mitch Tulloch)
Free eBook: Introducing Windows Server 2008 R2 (9 chapters by Charlie Russel and Craig Zacker)
Free eBook: Deploying Windows 7, Essential Guidance (10 chapters from the Windows 7 Resource Kit and 6 TechNet articles)
Free eBook: Microsoft Visual Studio 2010 (336 pages), written by Patrice Pelland, Pascal Paré, and Ken Haines)
I hope there’s something in this list for you to use and enjoy! (source)