The second month of the Cartographer's Annual 2008 takes a detailed look at creating new symbols for Campaign Cartographer, Dungeon Designer and City Designer. It connects to the January issue by doing several new Pete Fenlon style symbol as an example. That way you can extend the style almost without limits.
To make creating symbols quick and easy, the January issue provides specialized templates and drawing tools for the task: A whole drawing style just to create symbols! The pdf guide to creating symbols covers many details, among them setting up your symbols for different styles of maps, control points, varicolor, symbol attributes, and splitting symbols across sheets.
The style pack Symbol Catalogs includes