In reply to RobScotland:
I've got copies of most current instructional books and aside from the two already mentioned, I can't immediately think of any others. I don't think there is any generic and recent source of information specifically on protection. For very specific questions, researching online is likely to be the best option.
TBH other than the recent advent of Totem cams with better performance in marginal placements, rock protection hasn't really changed for at least 15 years since Wild Country reduced the available sizes of micro-cams with their Zero cams.
RP style micro-wires, offset wires and double-axle cams have all been around for many, many years although they have certainly become more mainstream with lighter, better finished and colour coded versions. However they still work in exactly the same way.
Slings are basically still slings although they are some newer materials. Edelrid Aramid slings are a useful new addition, knots can be untied more easily and they are better for threads. Mammut are also now selling more dynamic options.
Similarly ice screws haven't fundamentally changed since the original BD Turbo Express were launched many years ago. All that's happened is that the latest (really expensive) designs are much lighter due to using alloy shafts and hangers rather than steel throughout. There are also some super-short versions now available for the hardest thin ice routes. However they still place in the same way.
Might not be the most helpful answer but things probably haven't changed as much as you might think.
