To find an empty property you can try the following:

• Ask local estate agents. They might not have photographs of empty properties on display, but that doesn't mean they haven't got some empty houses for sale. You can find details of your local estate/letting agents in such as the Yellow Pages.
• Look in auction catalogues, as these are a good place to find empty properties that are for sale.
• Look at the following property websites, which specialise in empty properties:
  Empro.co.uk
  Renovate Alerts
  Propertyrenovate.com
  
• The Empty Homes Agency is a charitable organisation that campaigns to highlight the waste of empty property in England. It works with others to devise and promote solutions to bring empty property back into use.
• Check local building land that is up for sale. Some building land will already have a house on it. Often the house needs demolishing (knocking down) but sometimes it can be saved and rebuilt.
  Property Spy
  Plotfinder.net
  Self Build ABC
• Look around the area in which you are interested in buying a property. There are about 35 empty properties for each square kilometre in north London, and once you start looking, you'll see that empty houses are everywhere.