I've got some military field phones and wire stashed away. CW is okay, but I see it as a limited means of communication, because there aren't many CW operators....and yup I'm one of those 20 words per minute old time extra class radio operators, and I rarely use code anymore. Semaphores are another method, it seems to me the old Boy Scout manuals use to have a section on communications and semaphores.
For learning Morse code, I used 73 magazine code tapes (cassettes), beginning at 5 words per minute for the novice license, and progressing up to faster speeds. Once you have a basic understanding, then definitely listen to the CW portions of the ham bands. There's nothing like your first on the air CW contact.
One of my methods of contacting friends and family in the event of a major incident is the use of the Inreach Communicators, which use satellites to send text messages. My back-up is 40 meter or 80 meter HF using SSB. The fallback is PSK 31 on HF radio, mostly because it'll get through noise and low powered signals, but it does require a computer of some sort.
I don't know about the foghorns, but you could use one of the portable fog horns for signaling, much like hunters do with gunshots. For example, 3 shots indicates an emergency. For general signaling, or an alarm, an old time dinner bell, or one of those triangle dinner bells could be used.
