Redirection using index.php page

Hi,

I looking for someone to create a redirection using index.php.

I need to have links on my homepage that will direct users to the same page in different languages.

I need the URL to be in the format, mysite.com/?en to direct users to the page in the english language (english.php).
mysite.com/?ru should direct users to the page in Russian(russian.php) and so on.
I have the corresponding pages in the different languages.

You need to tell me the code to put in index.php to make that happen. Its enough if you show me how to do it for one language I'll do the rest.

Hope I've made things clear, if not just let me know.
Thanks.

Requirements

Need to be done asap.

Skills Required

Php