There was question about where to get info to plan a narrowboat cruise.
I got most of my information from the Internet. I had a key breakthrough when I realized that I needed to Google “narrowboat” rather than canal boat. I found a lot of information after that. But some of the good resources are:
Canal World Forums: http://www.canalworld.net/forums/index.php?act=idx The folks there will answer all of your question in whatever level of detail that you need. Very helpful.
Andersen Boats website: http://www.andersenboats.com/ We hired our boats from Andersen Boats. Their website has links to lots of information. And their boat was excellent and the service was great.
British Waterways puts out a book on canal boating: http://www.andersenboats.com/handbook.pdf
They also have a video on YouTube: https://www.youtube.com/watch?v=lXn47JYXs44
There are lots of other videos on YouTube also including the excellent series Great Canal Journeys: https://www.youtube.com/watch?v=8zRI7xwN_mU
As part of our planning and navigating I purchased an excellent book from these folks:
http://www.jmpearson.co.uk/
I used the iPad app eCanal to show our location on the canal in real time.
And, of course, the Ordnance Survey has maps and mapping apps for all of Great Britain. And these are excellent.
https://www.ordnancesurvey.co.uk/