What I use for maps in Shroud of Shadows requires Excel, Paint, and a Photobucket account!
-First, I made a blank map excel document. I made the height and width the same so that it looks like boxes. I use this as my template and never
save over it.
-Second, I create a map for combat or whatever it is I want to display for my players. I use borders to make walls and change the borders for doors or whatever I want.
If it is a combat map, using a coordinate system is quite helpful. If you use coordinates, I would suggest using both
letters and numbers. If not, it can be easy to mix up the X and Y axis and that is not fun especially in a PbP setting (it could be days to figure out what happend).
-Third, after I finish building my map I highlight the map in excel and "copy" it (I usually use 'ctrl' + C).
-Fourth, I open up a blank Paint file and "paste" it. Your map should be up and running. Save it somewhere you won't forget about it (I have a file in my documents that is devoted to my RPGs... it can get kind of crazy).
-Fifth, I upload it onto photobucket.
From that point all you have to do is set the link for your post and the map is there... just like magic