You can find this in the language file, installed at /language/xx-YY/xx-YY.com_jfbconnect.ini.
The keys for the emails are:
COM_JFBCONNECT_EMAIL_REGISTERED_BODY, COM_JFBCONNECT_EMAIL_REGISTERED_BODY_NOPASSWORD, COM_JFBCONNECT_EMAIL_REGISTERED_WITH_ACTIVATION_BODY, COM_JFBCONNECT_EMAIL_REGISTERED_WITH_ACTIVATION_BODY_NOPASSWORD, COM_JFBCONNECT_EMAIL_REGISTERED_WITH_ADMIN_ACTIVATION_BODY, COM_JFBCONNECT_EMAIL_REGISTERED_WITH_ADMIN_ACTIVATION_BODY_NOPASSWORD
-Melissa