The new ITA Matrix interface also shows fare rules. And AA website itself will show them once you get through to payment page (although they are much easier to read on ITA site due to better formatting). Fees for changes will be found in the Penalties section. Fares from AKL to US do not currently appear to have any change fees, but Australia fares to US currently have them on cheaper fares (the following are from ITA for QLX5CRN3 fares).