I handed in an assessment similar to that just last week. The Art Gallery of NSW website is a valiable source.
www.artgallery.nsw.gov.au > go to research>FAQ>who decides what to buy
There's a small section on curators there, and then you can always email the gallery itself. I did that and received a reply within a few days. Also, go through some art textbooks at your school. See if your school has one called "Interpreting Art" - that one has a small section on the gallery curator too. Good luck!