Okay, so I found where to look on my external hdd, unfortunately the file I need (in my users folder) isn't there, Windows 7 refuses to open it in regedit and will only open it in wordpad and it only comes out in gibberish code. So my question is if I had regisetered my game on the site (I think I did) how can I get the serial number?
If the things in the links I gave you don't work, I really don't know.
Did you try contacting EA ?
The AnswerHQ is about Users helping Users.
They can be found here: https://help.ea.com/contact-us/ask
Choose a category, a game and a platform for the contact options to show up.
If live chat is gray, change your country to US and make sure you're on US Business hours. It might also gray because they're very busy. Try later.
See this post if you have trouble with the site: http://sims3.crinrict.com/en/2012/10/how-to-contact-ea.html
