Bring to steam?

I just got back to this game since I stopped way before it's steam release due to a faulty graphics card that I had. I noticed that it is out on Steam now but it's asking me to buy it. I already purchased the game but can't figure out what email I used to purchase the game to get my purchase info and get a steam code. Can someone help me get either my email and proof of purchase of a steam code?

 

Thanks Nadeox1! I found out how by just spending a couple of hours digging around for my old steam account that it was connected to. Great Vids btw. This can be closed now!