If you cannot get the project in PLA-format, which would be the best option, you could try downloading the Graphisoft libraries from Graphisoft web page.
For the 8.1 Libraries you can find the latest libraries through the Download page.
http://www.graphisoft.com/support/archicad/downloads/
-Follow the 8.1 or earlier -link,
-then at the bottom of the page select your country code link,
-finally from the bottom of the version page click the link for downloading the latest libraries.
For the 9 version the Download page suggests that you use the AC9 internal updating system, but it seems that something is there for download also. There's no direct from the Downloads page, but I could find something through google and some url-poking.
The usa library update for example seems to be downloadable from url address:
I'm not sure whether these are complete libraries or just update patches, but the file size suggests that they might be complete libs.
I also don't know which localized version you are seeking, so if it's not usa, you could try replacing the "usa.html" part with appropriate country code.
Note that there might be more direct ways to get to the AC9 library download pages also...
Hope this works for you.
