Ok, if you can't get into wp-admin you need to try to reset your credentials. If you get a message saying that the email doesn't exist, and you're sure that it does, then the odds are your account has been removed by the hacker. You're going to want to log into your host administrator panel, access your database and manually overwrite the users. Some guidance on that here: http://codex.wordpress.org/Resetting_Your_Password
You can try searching for it via GREP in terminal. Its often not just one file, often all your JS files to include those in your theme and core files.
Happy hunting, let me know if this helps.