@Obi Wan
The one in my drop box is a Photoshop CS 5 file, if you don't have photoshop try the png files I attached to the original post here.
I'm no prop maker, and haven't put any great thought into any of these techniques or the advantages or disadvantages of them, but this is the way I've aged the paper:
The best start is printing the image out on some nice thick, textured paper, rather than regular printer paper. Then you can use coffee, tea and/or lemon juice to give it that "old paper" colour. You can use a spray bottle, a soft brush or just dip the map in or pour the liquid over it.
One cool trick is sprinkling a few granules of instant coffee which will dissolve into the page when wet and look like spots that sometimes appear on old paper. You can also go around the edges of the page with a lit match or a lighter. Another trick is to put it in the oven (I put it on at 170 degrees Celsius) to make the paper feel stiff and brittle, but you must watch it like a hawk or your map might catch on fire very suddenly.
You'll probably also want to add various folds and tears to make the map looked well used, I think it's best to add these before you age the map with liquid, or as you do it. That way the liquid will create different effects in the creases and tears.
It's a lot of fun to do. There are some nice long discussions on aging in these two threads:
http://www.therpf.com/f40/how-do-i-make-paper-look-old-105239/
http://www.therpf.com/f40/aging-paper-169075/index2.html
and on this site, which is linked to in one of those threads:
Ageing