For maps, I'd just suggest pencil/paper, or if you need something digital then go with any free graphics tool of your choice; candidates for that are GIMP or Inkscape.
There do exist free GIS tools, such as Quantum GIS, but I doubt that you're worried about creating maps that are defined in a terrestrial coordinate system - I can only see this being relevant if, for example, you're concerned about the distortion involved in different projections of continent-sized geography.
If by campaign maps you mean something that's easy to do an online campaign, and image files don't work, you can try looking into http://www.maplib.net/
. It's basically google maps on a custom image file you upload.
GIMP, Inkscape, and Quantum GIS are found at the first search results for each item.
I don't have any suggestions for timeline software, sorry.