List of registrars certified to to TE certifications can be found on the RAB's Website.
Address is www.rabnet.com
Go to QMS Registrars, Registrar Directory, and go into the Other Qualification window at the bottom of the form and select TE Qualfied.
Regarding your second question, DaimlerChrysler is requiring registration by 7/31/00; that is the only one requiring it to my knowledge.