Excel to return looked up values from drop down list?

[riteoh]

I have a series of Australian Postcodes, that can have multiple locations listed. EG.

2000 Sydney
2000 Bankstown
2000 Lismore

The locations also have other values listed against them, in 5 columns.

I need to write a lookup that will prompt the user to select the location from a postcode, and when the location value is selected from (drop down list?) the values against those locations returned.

So for example, then Value in Cell A is 2000, Cell B will return a drop down list of Sydney, Bankstown, Lismore, and when this location is selected, the values recorded in Cells C, D, E, F and G against Lismore the drop down list selection) are returned.

Have no idea where to start. Ideas please?

My excel file is attached, however 75% of the data has had to be cut out due to size limitations. The front page however should give an idea of what I need to do.