I don't think Google-fu is your problem - you just need to spell Zeppelin correctly! Once Google has caught onto what you are interested in, it seems to give you better hits - for example I just found a nice steampunk blog which just happened to have an article on airships...
Put 'zeppelin airship' into the google search engine, select 'images' and you should have a few plans amongst all the pics. Some links that may help also are:http://www.airshipsonline.com/airships/index.html
which covers British airships but the ill-fated R38 was based on knowledge gained from the Zeppelin program after the Armastice in 1918.
Another good site is:http://www.airships.net/
reminding us that this month was the 75th anniversary of the Hindenberg disaster (disaster in that it put the kiss of death on commercial airships - not in the normal sense as there was surprisingly high survival rate considering the pictures and the fact that it was a catastrophic aviation incident.)
As to your question about modern materials, power plants etc, your search on Zeppelin will give you results for Zeppelin NT, a new company which builds airships today in the same place they built the original ones! The new ones are non-rigid, or possibly semi rigid, in that the shape is maintained by gas pressure inside the envelope (the definition of non-rigid). The material it is made of uses carbon fibre and probably aramids, something like Kevlar which may well contribute to the overall shape, so semi-rigid may be correct. I make the point because this separates Zeppelin NT from Count von Zeppelin's earlier versions which were rigid airships. This means that their shape and structure was mechanical in nature formed of lightweight metal frames. The hydrogen lift cells flew inside this outer shell, tethered to the inside frames. New airships also use light piston engines turning ducted fans which can be steered and rotated to add control. The idea of rotating propellors is not new however and was certainly used on British airships during the First Great War.
So, that should give you a start. The Wiki articles will give you a lot more background on different manufacturers of rigid airships that were built in Germany - like the Parseval and the Schütte-Lanz, which had a wooden frame.
Hope that helps get you started.