As of May 10, 2006, all of the documentation for the OntoViz Tab has been moved to the Protege Wiki:

http://protege.cim3.net/cgi-bin/wiki.pl?OntoViz

This Web folder should remain in place to hold all of the image files that the documentation on the Wiki uses.

Old versions of the OntoViz Tab can be downloaded from the Protege Subversion Repository:

http://smi-protege.stanford.edu/svn/ontoviz-tab/tags/