how to collect user credentials and store in sql server database.

Question

i have to build a ranking system for the artifacts most visited by the viewers
and the visitors have to be unique.the articles are displayed by searching the intranet by a search engine. i have developed the database to store the url and the clicker ip or username. now the problem is how to track the username or IP address from the browser itself and load it in the database along with the URL visted by him. this application has to be loaded on the intranet.

please help me as to how this can be done. you can either send me an code excerpt or an article to implement this.

suraj