If you remember your security question and answer, you can retrieve your username via the "Forgot your Credentials" link at your Tracker website's login screen.  Select "I forgot my username", enter the email address from your Tracker profile, then click Submit.  The system will display your security question.  Enter your answer then click Retrieve Credentials.  You will receive an email in the email address on your Tracker profile with a link to reset your username and password.