Software

Computer-Assisted Wargames Enterprises - A system for running campaigns. Offers screenshots and sample games.
http://www.compassistwargames.com/

Trenchlight Software - Creators of the LordCraft Army Management System that makes customisation and collection of small or large wargaming armies easier.
http://www.trenchlight.com/

Berthier Campaign Manager - Software that allows umpires or players to manage small or large scale campaigns for miniature battles.
http://delyall.tripod.com/berthier/berthier.html

Army Builder - A versatile support tool for miniature collectors and wargamers. The software allows you to create, manage and organise small to large armies in many wargames.
http://www.wolflair.com/

The Forge - Provides a quick, easy and free way of creating army lists for your favorite wargames.
http://www.thedigitalfoundry.com/forge/