The National Environmental Science Program's Marine Biodiversity Hub supported a project to quantify underwater noise from ships in Australian waters, with the ultimate goal of guiding the assessment and management of noise impacts on marine fauna. As part of this project, ship noise was recorded and archival recordings of ships from the Integrated Marine Observing System (IMOS) acoustic observatories were analysed to build a catalogue of ship noise signatures in Australian waters. These signatures will then be used to inform a spatial model of ship noise around Australia. This technical report will be of interest to researchers working on ship noise, and presents the field recordings and the methodology developed for computing ship source spectra and source levels. The results of applying the software to recordings from an initial set of five IMOS deployments spanning a total of 1463 days are presented.