I am trying to learn Silverlight 4.0...i have 3+ years of Exp in .NET but do not know about silverlight... So request you to suggest me how to start to learn Silverlight 4.0...
Google is your best friend. There are so manny resources available for Silverlight, so that is is impossible to list them all here. Some of my personal recommendations are
And when you think you have a good understanding of the workings of silverlight / WPF you can switch to the MVVM pattern:
http://csharperimage.jeremylikness.com/2010/04/model-view-viewmodel-mvvm-explained.html