NPWS put out this
excellent PDF last year with details of the major routes through Wollemi and any private landowners you may need to contact.
Man I called a lot of people before that trip
Apparantly sections of trail between Glen Alice and Widden are closed:
http://nationaltrail.com.au/closedact.html
I have been meaning to find out if that status has changed or to where that it's actually a problem, or even if it's just "proceed with caution" or "nah you have no hope/dangerous"
There is apparantly a loop that's not totally mapped that links putty up through to glen alice trail via army road, and back via hunter main trail. A certain magazine editor has done it, I've heared rumours of others and seen photos, I can't link it on a topo and I've heared others try and fail to find the trail. Used to be a popular 4x track though as I understand.
Of the sections of trail I rode, I can probably still give you some fairly accurate route notes/cues from the top of my head ( I remember "things" like that)
Have a look at the GPS plots from the Link Flynny gave and the Flyer Ed posted. The national parks guy did that flyer basically because of my discussions with him. He seem pretty good to talk to and is worth calling if you plan to head through. He had some pretty good knowledge not only of the trail conditions but of places to get water and the like. I can possibly still remember the exact spots but it may be dependent on conditions. Semi potable water wasn't an issue when I went through but YMMV
I'm keen to do that rip S-N again with some modifications. I now have a rough sketch from the end of watagans through to new castle that takes in some parks, tracks, and Glenrock. I also know there's some primo single track in Rydal that'll potentially link rydal into Lithgow. IMHO a better detour than the BNT main route. A better route through the back of Hampton and out of Canberra still eludes me, but that could just be a matter of time and some local knowledge...
Feel free to give me a buzz, or post here if any of that raises more questions than answers...
Cheers
Spoonie