URL rewriting with using web.config

Hi All I have created a simple html website.
right now it is URL is like http://localhost:8080/mycontent/myproject/sitename/en_us/index.html.
what I want is, if User types http://localhost:8080/sitename it should open the http://localhost:8080/mycontent/myproject/sitename/en_us/index.html.
URL will remain the same (http://localhost:8080/sitename( so i have to write a rewriting rule in web.config and it should be dynamic.  like i can create another site mysite2 and page structure will be the same for site 2 also.  so http://localhost:8080/sitename2 it should open the http://localhost:8080/mycontent/myproject/sitename2/en_us/index.html. 
My web.config is on below loctaion. http://localhost:8080/ (web.config) and i have to do by web.config only.
Please ask if any doubt.
Thanks Vishwaraj