A Nerd's Eye View
A fantastic site for geocoding addresses - and it's free:
The example below is taken from the list of Lloyds TSB and Cheltenham & Gloucester branches that will be transferred to the Cooperative Bank under the Big Branch Sell-Off. A full explanation of the story can be found here. However, it took less than 10 minutes to create the example map below.
View Lloyds TSB, Cheltenham & Gloucester Branch Sold in a full screen map