Microsoft Translator offers great tools for web developers. With the Microsoft Translator Widget you can add translation to all of the content of your site, giving the user control over what language they read your site in.
With the Microsoft Translator API you can get access to our service allowing you to translate any user generated or other text. In this walkthrough you’ll learn how to use both of these, adding a widget to the master page of an ASP.NET site, as well as how to sign up for the translator API and use it in your ASP.NET code.
The walkthrough takes you through everything you need to know, including where and how to get the free Visual Studio tools for web developers, signing up for the API, generating a widget and writing the code that you need to access the API.
You can read the complete walk through here: http://blogs.msdn.com/b/translation/p/webapptranslator.aspx