CREATE TRIGGER delUsers
   ON  db_users
   AFTER DELETE
AS
BEGIN
   -- SET NOCOUNT ON added to prevent extra result sets from
   -- interfering with SELECT statements.
   SET NOCOUNT ON;
EXECUTE
   MSDB.dbo.sp_send_dbmail @profile_name =  'Mail Profile 1'
     ,  @recipients = 'me@email.co.uk'
     ,  @copy_recipients =  ''
     ,  @blind_copy_recipients =  ''
     ,  @SUBJECT = 'User Deleted'
     ,  @body =  'User Deleted'
     ,  @body_format =  'HTML'
     ,  @importance =  'Normal'
     ,  @sensitivity =  'Normal'

END
GO

Delete
From
    db_users
Where
    UserName Like 'A%'