Adding new postal zones

I need to add more shipping zones which calculate the shipping cost. Australia post now has 7 different zones and Zencart only allows for 3 zones. How do I add more shipping zones to the shipping module?

I assume that you are referring to the builtin "Zones" shipping module???

If so, download this file to your PC and open it in a code editor
/includes/modules/shipping/zones.php

At about line 113 there is this line that you can change to reflect the number of zones required
BUT also read the comments at the top of the file for other edits that might be required

      // CUSTOMIZE THIS SETTING FOR THE NUMBER OF ZONES NEEDED
      $this->num_zones = [B]3[/B];

Colour Streams:

I need to add more shipping zones which calculate the shipping cost. Australia post now has 7 different zones and Zencart only allows for 3 zones. How do I add more shipping zones to the shipping module?

I may be speaking out of place here, but do you seriously believe this to be a viable/practical method for these quotes?

As well as this new change in zones, I assume you are aware that there have been no less than 5 changes to these rates in the last 12 months alone? Keeping the tables updated could be a very time consuming process.

If that wasn't bad enough, Australia Post post only provide tables up to 2kgs in weight, anything more than this has a cost per additional 500gm applied (which also varies between zones). This means you'll either need to create your own additional tables for quotes between 2kg & 20kg (the max allowed), or modify the zones code to calculate these on demand.

All things considered, you'll probably be better off using one of these modules instead:
http://www.zen-cart.com/downloads.php?do=file&id=1138
http://www.zen-cart.com/downloads.php?do=file&id=899

I fully appreciate why neither of these options may not be suitable for your needs though, in which case please ignore this input.

Cheers
Rod

Disclaimer: I am the author/developer of one of these modules, so I'm not entirely unbiased, even though I'd probably make the same suggestions even if I had no association with them at all.