I know very little about architecture myself, but there is a great deal of information on the Internet about the subject. I am going to include a few links to sites you might find interesting and informative. I will include a short description of what is on the site for each one.

Architecture Timeline: "This page provides a quick history of architecture in the Western world, from prehistoric megaliths to modernist skyscrapers. Follow the links to find articles and photos for each period and style."

Architecture of Europe: An alphabetical listing of hundreds of architectural sights in Europe. Each listing is a a link to a page giving you additional information about the building and often includes pictures of the building.

Architecture of cathedrals, basilicas and abbey churches: A long Wikipedia article about this prominent form of architecture that can be found throughout Europe. The article includes many pictures and descriptions

A Digital Archive of European Architecture: From pre-historic through gothic to 20th century, there are lots of pages full of pictures and information about European architecture.

Enjoy your architectural exploration.