Found some strange refering urls in my logs

[Aquarius]

Browsing through my logs I found these refering urls. I own thepornebook.com, so the referings are from my own domain, the strange part is that those documents do not exist in my site and never had.

http://thepornebook.com/main.php
http://thepornebook.com/index.php
http://thepornebook.com/phptest.php
http://thepornebook.com/ccbill/index.php
http://thepornebook.com/index2.php
http://thepornebook.com/index1.php
http://thepornebook.com/ccbill/ccbill.php
http://thepornebook.com/link.php
http://thepornebook.com/tour.php
http://thepornebook.com/phpinfo.php
http://thepornebook.com/images/index.php
http://thepornebook.com/test.php
http://thepornebook.com/test1.php
http://thepornebook.com/page.php
http://thepornebook.com/test2.php
http://thepornebook.com/links.php
http://thepornebook.com/index.php3

Someone has a clue?