"Pan Am flight PA6"
That's a rather exceptional example, the plane took nearly 5 hours to plan its ditch and found a coastguard vessel to follow for a while. Hence the many pictures of the actual ditching.
The reason you don't hear about water landings far from a coast line these days is that modern commercial airliners generally fly within gliding range of land. For the ones that can't glide after an incident, there's generally been a catastrophic failure that means they probably won't be doing a controlled ditching.