It gets a little confusing when we have to type everything to each other. So let's make sure we both understand. I checked and sims3.com is the same as thesims3.com. So, whatever your username is on sims3.com should work on the other one, too. You need your user name (for me it's my email address) and your password to log into your account. Are you able to do that at all?
Also, do you have Yahoo Instant Messenger installed on your computer? If you do, we can chat using that instead of posting on the forum. It might be a little quicker and easier to understand. Send me a private message if you do have Yahoo Instant Messenger and I'll give you my user name in private. I won't be able to do it right now because I have to get to bed soon, but I would be able to chat with you tomorrow.