but could you please illustrate how anyone managed to consult notam's before the days of internet? Are those methods still available today?
I think the short answer is they didn't.
In my PPL days (2000/01) the instructor got a local briefing by fax and pinned it on the wall. Of course nobody present flew past the nearest crease on the chart... so this was OK. Those who might have been going places were not around because most schools don't like experienced PPLs hanging around, upsetting the instructors
In 2000/01 a pilot going places probably just got away with it... There used to be phone numbers which you could call for a briefing, but I have never met anybody who used to call them. And realistically there are only about 50-100 TRAs around the UK each year, mostly airshows, and the chance of a random pilot busting one is quite small, and this is probably how it "worked" all those years. Everything which is not an RA is fair game for a bust and nothing will be done about it because no law was broken.
Then a number of things changed.
(1) After 9/11, The French set up the prohibited areas around their power stations. I busted one of those in 2003, but narrowly escaped major hassle a) because I did not land in France and b) because the ais.org.uk database was crap, and c) because the French IGN charts did not show them.
(2) UK ATC set up the ais.org.uk notam database and this became everybody's source for going places. You could do a Narrow Route Briefing which remains to this day, and works fine. This became usable c. 2003.
(3) Because of the notam database, everybody and their dog who was authorised to generate notams (which was, and remains, everybody and their dog, illiterate or otherwise, but always awfully self important, especially if in the military) started generating masses of notams, mostly irrelevant and mostly just a pollution of the database... but you have to read through this garbage when you get the briefing. I bet the notam volume has gone up 10x to100x between 2000 and 2010, while the number of actually meaningful notams has remained the same.