Shipping Nightmare - UK Postcode Solution?

[Kegless.co.uk]

Background
Hey guys since I have been trawling the net extensively and this site for weeks searching for a solution to my shipping issue to no avail. I am a store owner so of limited techie knowledge. My cart (Version 1.2.7) was set up by a third party developer and was basically told it could do everything i wanted it to do, but I have been having difficulties in achieving this as the solution they provided was not very pretty and required a lot of management.

Problem
Basically I am operating a keg hire company and this is more service than product based as equipment is also required so ensuring availability in an e-commerce product based environment has not been easy as you can appreciate. That said it is my shipping that is the main issue.

With the nature of the service delivery and collection is provided by my firm. I have a free delivery area for the Edinburgh area roughly the EH1-17 postcode areas, outside that it is based upon their distance from our location. I have an excel spreadsheet of the Royal Mail postcode address file (PAF - just the 2,500ish out codes not full address file so only about a 1.2mb excel file) and by using simple trig calculated the distances of all postcodes from our location. As we have to drive 4 miles for each mile the client is from us due to two return trips we are unable to charge delivery by county etc.

From the PAF we have assigned a delivery charge for every 'out code' i.e. the first part of the postcode before the space (e.g. EH14 ###), therefore EH1=£0, EH2=£0...EH52=£27, EH53=£34 etc. As our delivery charge is about £2 per mile radius there is only about 150 postcodes (of the 2,500 in the file) that we actually need to be able to calculate shipping for.

Question
My question is therefore...can the PAF (or the 150ish postcodes we need be incorporated in some way so as to include the delivery charges in the order costing process. I cant see a way that it would work based upon existing payment/shipping mods without putting a list of 150 postcodes on the delivery area page.

Ideal solution
Ideally the shipping address would automatically check the user entered postcode against the charging structure attached to the postcode and either display free delivery or the correct associated charge for that postcode and add it to the order total. The clients would also be able to check the delivery cost without having to go through the order process, thereby stopping the flood of emails asking for delivery quotes that don't result in orders.

Satisfactory solution
A text entry box by which customers can input their postcode/select from a drop down list e.g. the shipping estimator window, and instantly display what the charge would be and the page can inform customers that the delivery charge is payable in cash upon delivery.

Additionally
For any developers who may wish to help me and other zenners out I have included a link to my excel PAF file http://www.mediamax.com/kegless/Host...odes-Towns.xls which I have already tweaked to produce the output i wish and simply needs some form of a zencart integration.

For anyone else out there wishing to use this file for their own shipping purposes please feel free, in 5-10 mins you can have it calculating your shippping costs to any postcode in the country based upon distance from any location in the UK.

Thanks
I would like to extend my wholehearted thanks in advance for any help on this issue and for the help a number of other forum members have given me by making their knowledge available to other zenners.

Paul McCaffrey

[robbok]

I don't know if this will help, but I am working on a similar scenario(except my client offers free localised delivery for orders over a certain price), and I have installed Conor's region table mod.
A run through is here:
http://dev.ceon.net/web/zen-cart/regiontables/

The actual mod is available in the download section.

The mod allows you to set multiple zones, each with their own table rates, plus the zones can be set either by distance from the store or by UK postcodes.
Hope this helps,
Rob