How do I create hierarchical select for state, district, city, and location using AHAH? I have a site for Indian tour places where I need to add the information for the "Location" content type.
For example, in http://www.indiantourplaces.com/andhra-pradesh/hyderabad/hyderabad/saroornagar-lake-51.htm we have the information for the location "SAROORNAGAR LAKE" which is located in India (country), Andhra Pradesh (state), Hyderabad (district), Hyderabad (city). I want to create all the above state, district, city as different nodes, and when I add the location details, I want to first select the state; then another list box will be populated with the list of districts which are present in that state, and once the district has been selected, another list box will be populated with the list of cities present in that district.

I am stuck up with this from may days.
It seems Hierarchical Select does exactly what you need.


  This module defines the "hierarchical_select" form element, which is a greatly enhanced way for letting the user select items in a hierarchy.
  
  Hierarchical Select has the ability to save the entire lineage of a selection or only the "deepest" selection. You can configure it to force the user to make a selection as deep as possible in the tree, or allow the user to select an item anywhere in the tree. Levels can be labeled, you can configure limit the number of items that can be selected, configure a title for the dropbox, choose a site-wide animation delay, and so on. You can even create new items and levels through Hierarchical Select!