I am really interested in PowerShell for SharePoint Administration. Please help me with some books, sources or tutotials.
A great sample of PowerShell scripts developed/managed by Microsoft MVPS and employees for SharePoint farms (WSS or MOSS) management.
For using PowerShell with SharePoint - there are tools, code libraries and some good books out there:
This is a great blog on using PowerShell with SharePoint: http://get-spscripts.com/
For Real-World SharePoint PowerShell scripts:
There is a PowerShell command builder tool for SharePoint developed by Microsoft. It has been of great help to me. Try it: Windows Powershell Command Builder for SharePoint