Eu acho que você deve ter perdido alguma coisa, deve estar em todas as grandes distribuições. Aqui está o Fedora 20:
> yum search gnustep
[...]
gnustep-gui.x86_64 : The GNUstep GUI library
gnustep-make.x86_64 : GNUstep makefile package
gnustep-back.x86_64 : The GNUstep back-end library
gnustep-base.x86_64 : GNUstep Base library package
gnustep-base-devel.i686 : Header of the GNUstep Base library packes
gnustep-base-devel.x86_64 : Header of the GNUstep Base library packes
gnustep-base-doc.noarch : Documentation for gnustep-base
gnustep-base-libs.i686 : GNUStep Base Libraries
gnustep-base-libs.x86_64 : GNUStep Base Libraries
gnustep-examples.x86_64 : The GNUstep examples
gnustep-filesystem.x86_64 : The basic directory layout for GNUstep packages
gnustep-gui-devel.i686 : Header files for the gnustep-gui package
gnustep-gui-devel.x86_64 : Header files for the gnustep-gui package
gnustep-gui-doc.noarch : Documentation for gnustep-gui
gnustep-gui-libs.i686 : Libraries for gnustep-gui
gnustep-gui-libs.x86_64 : Libraries for gnustep-gui
gnustep-make-doc.noarch : Documentation for gnustep-makegorm.i686 : The
GNUstep graphical interface builder
gorm.x86_64 : The GNUstep graphical interface builder
[...]
Aqui está o Ubuntu 12.04 LTS:
> apt-cache search gnustep
[...]
gnustep - The GNUstep Development Environment -- user applications
gnustep-back-common - GNUstep GUI Backend - common files
gnustep-back-dbg - GNUstep GUI Backend - debugging symbols
gnustep-back0.20 - GNUstep GUI Backend
gnustep-back0.20-art - GNUstep GUI Backend (art)
gnustep-back0.20-cairo - GNUstep GUI Backend (cairo)
gnustep-base-common - GNUstep Base library - common files
gnustep-base-doc - Documentation for the GNUstep Base Library
gnustep-base-examples - Examples using the GNUstep Base Library
gnustep-base-runtime - GNUstep Base library - daemons and tools
gnustep-common - Common files for the core GNUstep environment
gnustep-core-devel - The GNUstep Development Environment -- core development
gnustep-core-doc - The GNUstep Development Environment -- core documentation
gnustep-devel - The GNUstep Development Environment -- development tools
gnustep-dl2 - Objective-C Classes needed for Database Access
gnustep-dl2-postgresql-adaptor - gnustep-dl2 adaptor to connect to PostgreSQL
gnustep-dl2-sqlite-adaptor - gnustep-dl2 adaptor to connect to SQLite
gnustep-examples - GNUstep example applications
gnustep-games - The GNUstep Development Environment -- games
gnustep-gpbs - GNUstep PasteBoard server
gnustep-gui-common - GNUstep GUI Library - common files
gnustep-gui-doc - Documentation for the GNUstep GUI Library
gnustep-gui-runtime - GNUstep GUI Library - runtime files
gnustep-icons - Several free icons for use with GNUstep and others
gnustep-make - Basic GNUstep Makefiles
gnustep-make-doc - Documentation for GNUstep-make
[...]
E a saída debian wheezy é semelhante.