How to see a list of the pages in a namespace
To see a list of all of the pages in a namespace (the main namespace has over two million), click on Special pages in the toolbox menu on the left side-bar of your screen. At the top of the list that appears is the entry All pages. Click on that, and a pull down menu (to select a namespace) and a search box for entering a starting pagename appears. The namespace listing will start at whatever spelling you place in the searchbox.
Read more: Wikipedia:Special pages
See also: Wikipedia:Namespaces