1. The New York Information Technology Center
2. Economies and Diseconomies of Scale and Year 2000 Compliance
3. Australian Competition and Consumer Commission Merger Guidelines
4. The DeBeers Diamond Cartel

Costing Definitions and Concepts (provided by Ben Johnson Associates, Inc.)
A good discussion of various measures of economic costs.

Related resources:

Other economic resources
This page contains a set of links to economic resources that may be of interest to introductory economics students.