The official IBIS Open Forum web site is located at:
http://www.eia.org/EIG/IBIS/ibis.htm
This site contains articles introducing IBIS, text of the IBIS standard, examples of IBIS files, and tools such as the golden parser. The site also links to other web sites devoted to IBIS.
Other web and ftp sites that have information about IBIS are:
http://www.eda.org/pub/ibis/
http://www.vhdl.org/pub/ibis/
ftp://ftp.eda.org/pub/ibis/
ftp://ftp.vhdl.org/pub/ibis/Star-Hspice Manual - Release 2001.2 - June 2001