I would also recommend to buy it, if you haven't. ;-)
I have the Houghton Mifflin paperback edition of 2000, ISBN 0-618-05699-8, $15 US
OH !! Ive read it and I love the letters he wrote for his boys!! WHAT A WONDERFUL GIFT TO GIVE TO THEM EVERY YEAR !! And all the great stories ... I will read them for my children as well...