If you are interested in getting and running model versions now, check out the page on Getting and running code.
For the sake of introduction and discussion, I have created an aggregation of GTAP, and a simple version of the CGE with four industries:
I break out dwelling in order to make a point in the Capital section.
All data is described in the Data section. The scripts that are used to generate the AMPL code are described in Building a model version. The three main pieces of the code are presented and described in the AMPL Code section.
The Government and Capital sections describe some key elements of a basic CGE model, and expound on some potential issues.