Tom and others: until I can find out whether there is a key combination for 
sending an email to the entire address book, I think I have discovered a 
strategy that may work easier, and that is to use the "Reply All," key 
sequence which is control shift R.  Just hit that combination in an open 
email, cut out what you don't want to send and type or paste in what you do 
want to send, and it will go to your entire address book.  It's still a 
little bit of work, but it may get the job done.
Harvey