Airship? Your best bet would be to contact one of the airfreight thinktanks and ask for a not-too-detailed floorplan/layout for a project.
I swear, someone's going to take over the world with "for a project".
Regarding the freighter one - uhm, there's some stuff I found (4 years ago now, so long gone sorry) but a superfreighter/tanker won't give out plans due to industrial confidentially. (Translation, you can easily guess stresspoints and possible "weak points" if you were of evil intent and had some background in engineering. And they'd really not like that spread out too much. Or so the nice people at Mersk told me. After scenting bullshit and asking a shipbuilder, I found out that those plans are
expensive, no building firm's going to leave those online for someone to rebadge and resell.)
Basically, no supercap container plans for you, I'm sorry. The best you'll get is post WW2 construction stuff (now public domain) and retrofit to suit.
...or simply Google Image search "container ship plans" and get a ton.
http://picsdigger.com/keyword/ship%20plans/Specifically:
http://picsdigger.com/image/b806de7f/Also, global security has some rough stuff:
http://www.globalsecurity.org/military/lib...0-17-1/Appc.htmBut they're not strictly commercial, more semi-security/military.
There's this fan site as well:
http://www.gods-inc.de/macavity/IsleOfShad...icles/subs.html-> the commercial subs.
Oh yes, using those for our pirate campaign funtime...
If you're really desperate, you can try and farm one or two off of the respective shipping companies, but they're pretty low in useful info.
Oddly enough, even using a "no naughty pictures" filter for the GIS, there were a lot of naked men. Takes all sorts, I suppose...
-Tir.