gnet-spice-noqsi.scm is a "back end" for the lepton-netlist program, which is part of Lepton EDA. See http://gpleda.org/ for details on Lepton and lepton-netlist.
The version for gEDA and gnetlist is frozen. It is tagged here as geda-gaf-release-2.
lepton-netlist -L where/the/.scm/file/is/ -g spice-noqsi ... produces output in SPICE format. It is intended to allow the designer to produce schematics that can be used as input for both SPICE simulation and printed circuit layout. It supports this by providing flexible methods for mapping schematic symbol attributes into the parameters of SPICE declarations and commands.
For a tutorials and reference documentation see the Wiki.