Hi there Richard.
The maps I use are made by Astrovisuals,
www.astrovisuals.com.au, and are available from many astronomy shops and Australian Geographic. I think the set retails for about $25. The pack also comes with the maps on a CD plus other photos from NASA and other info. For the price I find them very good.
There is also another map and CD set for all the southern sky down to mag. 6 with brighter planetaries, galaxies, nebular etc. Great for quick referance and beginers. Also about the same price.
A4 sizes with water resistant coatings.