There are a plethora of interesting publications and papers to collect during your attendance, as well as your own personal shopping (it is serious sale time in New York !), so you might consider bringing an extra empty bag. Some CSW participants purchase extra suitcases to help cope. Remember, though, it is both expensive and frustrating to have to deal with the problem at the airport-not the best way to end a great experience of the UN and New York.
Rather than collecting hard copies of papers (which become heavy and costly in your return luggage), consider noting the URLs noted in the publications, that you can read/print when you return to Australia.