My favourite place for finding government publications and press releases which have disappeared from their respective department websites is the Ontario Legislative Library catalogue. One can run a simple search from the entry page:
or delve down a level to find the Guided Search and Command Search pages:
The fantastic staff at the Legislative Library ("The Leg") make a concerted effort to capture as many Ontario government documents and reports as possible and house them on their own "eArchive" servers. Access is directly from the catalogue record:
Are other Legislative/Parliamentary libraries doing this as well? Any other organizations?