Are there any third-party Templating Engines for Asp.net like we have smarty,savant for php ?
Your question does not explicitly states what "breed" of ASP.NET you are using, so I guess it is most likely web forms. If this assumption is correct, I would not recommend for you to replace the default view engine. In order to make good use of the build in controls, you really want to keep the abstraction where HTML like elements can be marked runat=server
and accessed from the server side code.
If you happen to use ASP.NET MVC, the picture is completely different. Here, there are lots of different view engines available - including NDjango, NHaml, Spark. If you are the type of web developer who care about the templating engines, you are likely to prefer ASP.NET MVC as a whole, and you might want to check it out before starting your next project.