I am looking for the location where drupal stores the LDAP server once it is set in the website.
By default Drupal doesn't store any LDAP server information. If anything is stored by other modules, it's stored in the database. Depending on different modules, these data is saved in different tables.
If you're using LDAP module for Drupal 7, you can find the settings in
If you're using LDAP module for Drupal 6, you can find the settings in
Looking at the ldap_servers module install file it looks like it stores the server settings in a table called ldap_servers.