Postcards of the Past
Some other postcard sites you may find interesting.
General Postcard Links
Postcard Pages - Information on postcard collecting, including lists of traders and fairs.
Reflections of a Bygone Age - Another site with a wealth of information on postcard collecting.
Ebay - a great place to buy old postcards.
Francis Frith - postcard publisher since the 1860s. They have an online shop selling books and prints of old postcards.
Dating stamps on postcards from the 1890s to the 1950s
Post Crossings - send and receive postcards to and from people around the world.