First of all… Download Windows PowerShell

Windows PowerShell® is a task-based command-line shell and scripting language designed especially for system administration. Built on the .NET Framework, Windows PowerShell helps IT professionals and power users control and automate the administration of the Windows operating system and applications that run on Windows.

Built-in Windows PowerShell commands, called cmdlets, let you manage the computers in your enterprise from the command line. Windows PowerShell providers let you access data stores, such as the registry and certificate store, as easily as you access the file system. In addition, Windows PowerShell has a rich expression parser and a fully developed scripting language.

Let’s get it!
http://blogs.msdn.com/b/powershell/archive/2008/12/30/download-windows-powershell.aspx