Oovee has kindly provided all you Steam clients a Backers Portal in case you did not recieve a key yet for downloading it from Steam.
Go to the Backers Portal and enter the email address you used and your zip(post) code.
You should then recieve a key for Steam. If not then find me on the Oovee forum and send me a pm, ill 'look into the matter then.
*upadte: added link to the Backers Portal *