Hi there,
you can read the rules
here, which are also available in english [Scroll down]. To sign up to the ETCC you have to find at least one teammate.
You can sign up your team on
this page. Unfortunately, it's only available in german, so I'll translate it for you:
1. "Wie soll Euer Team heißen?" = Your team's name.
2. "Bitte wähle dein Wunschfahrzeug, mit dem dein Team an den Start gehen möchte." = Select your car. [Keep in mind, that you can only choose a car, which hasn't been chosen by another team yet.]
3. "Name Fahrer #1/2/3/4" = The drivers Names.
4. "Für den Papierkram bitte noch eine Emailadresse" = A mail-adress for informations regarding to the ETCC.
5. "Was liegt noch auf dem Herzen?" = Anything you'd like to tell the race control. [Not necessary]
After the registration, the race control will send you the link to the ETCC-"office" and the passwords by E-Mail.
Remember, that you have to sign up your Team for each race separately.
As an alternative, you can join the public server, which is offered beside the official races. You won't need a password or team. However , racing in the ETCC with a team is much more fun.
I hope I could help you and I'm looking forward to see you on track. Good luck!
Linox