If you want to use OpenStreetmap data with mapnik to produce map tiles, I think the 'Manually Building a tile server' page in the link that Stephan sent would be a good place to start (
http://switch2osm.org/serving-tiles/manually-building-a-tile-server/) - that includes installing Mapnik, but the database handling stuff is all necessary because that is what mapnik uses to get the OpenStreetMap data. If you don't particularly want a tile server, just generate tile images, there is a python generate_tiles.py script that you can use instead of the mod_tile and renderd things, but you still need the database bits.
Hope that helps.