There is a pretty good topo map of McLean that you can buy at the store there when it's open. It shows all the trails, although the location of many trails on that map is suspect. I've wheeled some of them with my GPS on, and the location where the trail is plotted can be out by up to 1000 meters.
For Waiparous, there's a similar map (not a standard 1:50000 topo), but Waiparous has the advantage of numbered signposts that correspond to numbered points on the map. I can't tell you where to get that one, as I got it from another CJA member who was handing them out to the group at the first run I did in Waiparous. (a very good idea, BTW)