I'm wondering about the weight of the Boeing 747's fuselage.
The fuselage weight for 3/4 of a 747-300 Combi minus engines, fuel tanks, seats, catering, cargo handling, navigation gear, control surfaces, pumps, hose is 70,000 lbs, according to Big Imagination, the people that bought a 747, gutted it and took it to Burning Man. The 70,000 lb figure was used by the Nevada DOT to determine the oversized vehicle permit fee. If you add another 25%, you come up with roughly 93,000 lbs.
In comparison, a A 747-300 dry weight with engines, seats in airworthy condition is about 384,000 lbs.
I know this only partially answers your question, but every other source I have tried features the Operating Empty Weight (OEW), which is a basic working weight for each plane variant.
Good luck finding a better figure. I'd love to know myself.
A 2002 MIT research based on available public data breaks down the operating empty weight (OEW) of a typical commercial jet-liner as follows:
Simplified, a jet-liner is 1 part wing, 1 part fuselage, 1 part systems, and 1 part engines and landing gear.
While yes the 747 has an upper-deck, it won't skew the above by much, because the weight of the fuselage is carried by the wing, so the relation should hold.
Going by the 747-400 and its OEW, we're looking at a 46-tonne fuselage – note that the freighter versions (that have shorter upper-decks) are lighter by ~20 tonnes, but a big portion of that is the passenger-related items/systems.
P.S. 46 tonnes (~101,400 lbs) is close to @gwally's answer of 93,000 lbs. Using the OEW of the 747-300, the result is 96,000 lbs.