We did some sales tracking at ZoZa, but it was rather simplistic. Of course we did all the regular stuff - dumps of what sold what day, etc. etc. However we weren't required to do much in the way of demand analysis.
I think this was due to the Ziegler's distance from these techniques, and their wish to fly the company by their feelings. "We are the customer," was the regular response to any questions about market analysis.
Anyway, behind the scenes we did build some geographic and demographic sales reporting tools, as well as some source tools. The tech team wanted to know who the heck was coming to our site!
Any visitor from an Internet source we would tag via the link they used to get to the site. Otherwise we would simply ask in the Order Pipeline.
Once we started shipping print catalogs with Source Codes we were better able to track this crucial information.