readme: Document e-mail setup

readme.org

@@ -10,6 +10,22 @@ programs are gone (Awesome, cmus, fish, fzf, Mutt, newsbeuter, ranger, urxvt,
 zathura, zsh).  You can search for them before the git commit =README: The Big
 Emacs Shift=.
 
+* E-mail setup
+
+Emails can be particularly tricky to set up, so I think they deserve a dedicated
+section.  My configuration files:
+
+- [[file:.mbsyncrc][.mbsyncrc]] for =mbsync= from the ~isync~ project to synchronize mail mailboxes
+  over IMAP.
+- [[file:.notmuch-config][.notmuch-config]] for the email indexer.
+- My Emacs' [[file:.emacs.d/lisp/init-notmuch.el][init-notmuch.el]] for the user interface with the =helm-notmuch= extension for
+  searches with live updates.  (A must!)
+- My Emacs' [[file:.emacs.d/lisp/init-message.el][init-message.el]] to send emails.  I can afford to not rely on a
+  dedicated SMTP client (e.g. =msmtp=) since all my email accounts use the same
+  SMTP server.
+- My Emacs' [[file:.emacs.d/lisp/init-notmuch-sync.el][init-notmuch-sync.el]] and my [[file:.local/bin/homesync][homesync]] script to synchronize the user
+  tags (but not the automatic ones) under version control.
+
 * Setup
 
 For the list of programs I currently use, see the =.package-lists/= folder.