Odds are if you are on this site you are probably interested in building Silverlight applications. Here’s the rundown of what you need to get up and running.
What You Will Need
You will need either Visual Studio 2008, or the Expression Blend 2.5 Preview.
(For now, you will need Visual Studio 2008 Standard or above. Unfortunately it looks like the Express versions cannot author Silverlight content just yet.)
What Else You Will Need
(All of these are at the very bottom of http://silverlight.net/GetStarted/)
If you encounter any problems, Bradley Bartz has some great troubleshooting tips here: http://weblogs.asp.net/bradleyb/archive/2008/03/06/installation-tips-for-sivliverlight-tools-beta-1-for-visual-studio-2008.aspx
Starting Your First Project
Once you have all of those pieces installed you should be ready to create Silverlight 2 applications. Just Open Visual Studio 2008 and choose File -> New Project. Choose the Silverlight node and choose Silverlight Application. Give it a better name than SilverlightApplication1 and hit OK.
Once you do that there is one last question to answer, do you want to add a web site to host your Silverlight control, or do you want to have this page "automagically" generated each time you run your application.
Pick the Web Site option if:
Pick the Test Page option if:
Now that you are up and running you can start playing around with Silverlight. If this is your first time with Silverlight and WPF, Scott Guthrie has a great introductory walk through, or if you are interested in doing things with the Silverlight DataGrid check out these posts.