Media reports indicate concern that the website of the abolished Sydney Metro Authority is no longer publicly available. However, it has been cached by Google (3 Feb 2010 01:06:28 GMT).
I suggest the NSW government adopt the practice of some federal departments and retain such web pages at their original address, but add a header to indicate the material was no longer current. This practice was adopted when there was the first change of government after adoption of the web by government (I recall the interdepartmental meeting where it was discussed). This practice is also followed by some US federal and state agencies.
Also the National Library of Australia might like to put a copy in their Pandora Archive.
Obviously details of a failed project which wasted hundreds of millions of dollars is an embarrassment to the NSW government, but attempting to suppress the information is unlikely to improve the situation.