Create a Google Group (or Yahoo group) comprised of all the email addresses of your blog members.
Then go to Blogger Dashboard->Settings->Email
and enter your new Yahoo/Google Groups email address in the BlogSend Address field.
Any new posts will automatically be emailed to the group members.
You can do the same thing for all post comments as well, insert your
group address in Blogger
Dashboard->Settings->Comments->Comment Notification Address
field