title: Where can I find the assembly System.Web.Extensions dll?
body: <p>I'm messing around with some JSON and I'm trying to use the JavascriptSeralizer Class but I cannot for the love of god find a link to find where to add the assembly to my project. Someone help please! </p>
  
  <p><strong>Update</strong> 
  I'm using .NET 4.0 and its not in the .Net tab when you right click on references -> add reference in the solution explorer of Visual C# 2010.</p>