We are always surprised to learn just how much is out on the Web related to software measurement. We have listed the resources we have either used or think are useful.
 
Websites continue to come and go - we will attempt to keep only "live" links here.

Costar Software Estimation Tool from Softstar Systems is a faithful implementation of the COCOMO model that is easy to use on small projects, and yet powerful enough to plan and control large projects.

COCOMO II: COCOMO II is a model that allows one to estimate the cost, effort, and schedule when planning a new software development activity. The COCOMO Research Group at the Center for Systems and Software Engineering maintains this model and a suite of other models