The Australian Railway Historical Society have a DVD that you can buy for $79 called New South Wales Track and Signal Diagrams. It will give you all the track diagrams you want. It is available from bookshop at Central station. ARHS also have an online shop, although it is closed for upgrade at present. http://www.arhsnsw.com.au/bookshop.htm
You could also visit the Australian Railway Historical Society Railway Resource Centre at Redfern where you would be able to view track diagrams and photos. http://www.arhsnsw.com.au/resource.htm
There are two Bailey booklets, one of which has a CCSingleton diagram of Picton yard.
* Picton Mittagong Loop Line Railway
* Picton Mittagong Main Line Railway
Some second-hand copies may be available at the ARHS second-hand sale at 67 Renwick St., Redfern, open 1st Tuesday and 1st Saturday.
The CCSingleton article would be in a copy of Australian Railway History (formerly ARHS Bulletin).