The Geograph® Britain and Ireland project aims to collect geographical photographs and information for every square kilometre of Great Britain and Ireland, and you can be part of it.
http://www.geograph.org.uk/search.php?i=41689877
Photographic images of countries which can be selected by continent, then by country.
http://www.travel-images.com/
UK, Europe and USA images
http://www.freefoto.com/
Panoramic images
http://www.panoramas.dk/