We have just released a technical report detailing the inner workings of the Texas A&M WebGIS Geocoding platform. This report is available from the publications page on the Texas A&M GIS Research Laboratory website, or directly at the link in the following citation: 

Goldberg, D.W., 2009. The Texas A&M WebGIS Open Source Geocoding Platform. Technical Report No 11. Los Angeles CA: University of Southern California GIS Research Laboratory. Available online at: http://gislab.Texas A&M.edu/i/publications/gislabtr11.pdf.