Re Victoria State, GeoVic
http://www.dpi.vic.gov.au/DSE/dsencor.n ... 9FA1A?open provides a number of different mapping functions, the Forest Explorer and Explore Victoria On Line probably being the most relevant to our needs.
You need to open up the options and ensure the required details are checked but the overall quality is nowhere near as good as (say) the UK OS Maps on StreetMap. There also appears to be no WMS feature so it is necessary to take screendumps or clips of the maps and join them in a paint programme for manual georeferencing. The low contrast of the mapping also means even using the 5m grid, the detail can be somewhat blurred once imported to Trainz.
Where these maps do shine however, is that they seem to show most abandoned railway lines which are either not shown at all in Open Street Map, or due to the passage of time absorbed back into surrounding terrain and hard to follow in Google satellite view or Google Earth.
A compromise may be to use these maps to trace the actual route, but switch back to the sharper and more detailed TMS such as Open or Google before extracting into Trainz.