Crag includes the famous Taipan wall.
All boulder problem descriptions from "Grampians Bouldering" David Pearson & Chris Webb-Parsons 2009
From Mount Zero picnic area car park follow the tourist path marked with yellow arrows. You will know when you get to taipan. You will say 'wowzer' or something to that effect.
2014 bushfire update: most of this area is open but check http://parkweb.vic.gov.au/explore/parks/grampians-national-park for details.