You are good to start with Silverlight 4.0. I'm afraid that, you would need Visual Studio 2010. There are bunch of video tutorials available nowadays.
You can refer:
http://www.silverlight.net/learn/videos/silverlight-4-videos/[
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You can refer jesse's blog site. Very resource full.
http://jesseliberty.com[
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Once, you gain some expertise. Start learning MVVM frameworks such as MVVM light
All the best for your learning.