If you've forgotten your site password, click the "Forgot your password?" link on the login page to reset it. Enter your email address, then click Request.
If you no longer have access to the email address associated with your account, contact the Widen Central Support team. While Central Support isn't authorized to change email addresses or usernames, they can provide an email address where you can request an update to your account information so you can reset your password.
You can also create a new account, but note that past account history will be lost when doing that.