When I was learning to fly, as far as I remember the only time I saw all the documentation assembled was when I was preparing for the GFT. The club distributed sheets with the weight and balance data for all the aircraft which were available for routine flight planning. The POHs were available on request, but many people used the little A5 booklets you can buy from Transair etc covering the basic info for common types such as C152 or PA28.
I am now involved in group flying, and we give each new member a photocopy of the POH along with a checklist derived from it (as commercial ones are not available).
I have also assembled relevant data on the back of a flight planning sheet which gives weight & balance figures and graphs, fuel burn, landing and take off distances, plus the factors for calculating the TORA and LDA so that all the key information is to hand. This has been distributed as a .pdf file for members to print out and seems to work OK. We don't work every single thing out every time we fly, only if there may be a problem. But I suppose we should.
I know that the new JAR PPL has an additional exam for flight planning, so maybe all the new pilots coming along are more aware of these things.
It's already been a bad year for GA accidents and now with the hotter days comes degraded performance and plans to go further afield. Maybe we should all be revisiting these basics we all learned what seems like a long time ago, to avoid becoming statistics ourselves.
RD