I'll be short because the time of this deal has almost elapsed, so here's the link:
GOG.com
Just scroll down until you see the game, sign up to take it or login if you already have an account there.
After you do that and submit your email, you'll get the order confirmation within a minute.
Then go here: https://www.gog.com/account
And voilą !
http://i.imgur.com/SYJ2JOk.jpg
Enjoy !
