try here
Just remember that the BT part of the postcode is not the full postcode, it will either be BTX XYY, or BTXX XYY where X is a number, and Y is a letter. Each full postcode only covers a small number of properties, mine for example covers 24 houses, a small cul-de-sac of terraces.
It may be a bit more time consuming than you wanted though, as you have to click into each separately to find the name of the area, and it narrows them down further than just the first BT section