Manual accounts
From MoodleDocs
This authentication method requires the administrator to manually create all user accounts. It may be used together with the upload users tool (Site admin > User > Accounts) which uses a text file.
Can you arrange for an e-mail to be sent to notify Users of new accounts?
Not at the moment.
See Feature request here: http://tracker.moodle.org/browse/MDL-19390
See discussion http://moodle.org/mod/forum/discuss.php?d=117005
The discussion here: http://moodle.org/mod/forum/discuss.php?d=125000 suggests Moodle may send out e-mails under some circumstances with bulk upload of new users.