OT: how to set up a newsletter mailing list

[Josef Lowder]

.
What is the best way to set up a newsletter mailing list 
so I can send the same email message once a month to all 
of the email addresses (about 100) in my mailing list 
without using Cc: or Bcc:?  This would *not* be spam 
as these are email addresses of my own clients.

Someone has suggested either Dada Mail or Google Groups, 
but I have not been able to find a tutorial that explains 
step-by-step the best way to set up something like this.