How do i add towns to provinces (states) list

I have searched and not found a answer to my specific request.

I ship mostly to South Africa customers at present and i need to be able to define towns per province (state) due to a shipping agent that i use that do not work off the postal codes system.
Due to the postal codes that covers such a wide area there are some parts not covered by the courier company so the postal codes would render it pretty useless.

For instance i have a special rate for GT Gauteng Province (state), but not all areas which falls withing the Province are covered or considered as local.
Some other towns in the different Provinces (state) are considered an outlying area and attract additional costs.
I would appreciate help or ideas how to set this up. Perhaps there may already be a similar plugin that i can just reconfigure!

Hi,

The solution I can propose is to disable all the state zones via the menu System>Zones, and create new state zones, one per city, add them as sub zones of your country, and then change the custom field "state" to "city in south africa" via the menu Display>Custom fields.
That way, your users will be able to select the country and the city for south africa and you'll be able to use these city zones in your shipping methods "zone" restriction options.
Otherwise, it would require a custom made shipping plugin to handle the city restriction. I don't know of any esy way to do that except to have it developed by a skilled PHP developer.