I got a reply from Dave De Santi (referring on to Duncan Chalmers who seems to be the current computer/music scanning guru of the Sydney Folk scene - will buttonhole Duncan when I next run into him):
"Duncan Chalmers had done some work with reading from sheet music and then tidying up. We did talk about it the Computers and Music Workshop.
There were a number of softwares - MusicScan, MidiScan with varying features.
Duncan might be able to comment."
I have not tried any of these as I don't have a suitable scanner at home. Until now I have just keyed the tunes into MusicTime and regarded it as part of the learning experience, but a workable music scanning package could seduce me away from that view.