List Towns From Postcode

[shaundunne]

Im looking to find the closest UK towns - listed by distance when the user submits their postcode.

I have 3 MySql tables.

Table A includes:

Full postcode
Northing Londitude
Easting Londitude

Table B Includes:
TownID
Northing Londitude
Easting Latitude

Table C
Town ID
Town Name

I don't even know where to start with the mathmatics of this - been looking around but can't really find anything. Can anyone help out?

I need to List all of the towns within thirty miles.

[walterquez]

Check this site; http://en.wikipedia.org/wiki/Haversine_formula

[wtg21_org]

i think there need to be same id's to towns from b table AND c table ...

why you use 3 tables when you can use max 2 tables