Christopher Schmidt has put up an excellent screencast on Mapping Your Data where he walks through getting free data from the CIA world fact book, and carrying you through to generating web-based 'slippy' map in OpenLayers. Along the way he uses the powerful
i,f somewhat cryptic, QGIS and the very difficult, but even more powerful WMS.
It's a great tutorial, an very short owing to the power and ease of use open tools have developed into. Open tools can now begin to accomplish real GIS work instead of being solely for the StoryMapper or Neogeographer.