A note about versions of
Spice2 is the FORTRAN version on which many commerical versions have been based. The last Berkeley release was version 2G6. Its sources and binaries may be found in archives for Linux and MSDOS.
Spice3 is the "c" version which has an interactive command interface and X11 graphics support. The last Berkeley released version is 3F4, but patches on the Berkeley archive for it lead to a version often called 3F5 but sometimes still called 3F4 (as with an old Redhat rpm package).
The ngspice project is based on Berkeley Spice3. If you wish to build your own Spice3 from source, get the ngspice latest version.