web data mining , from a web site without knowing the url

Please,How do i get a data from site e.g www.xyz.com I know the site has this data e.g a house image in the form of a download link . The challenge is i don't know the URL of the image all i know is the site plain url (xyz.com) .How do i get the URL without crawling the whole site assuming the site doesn't have a searchbox too . I know this is a web data mining problem but i really don't know an effective way to approach it .I thought about crawling the whole website but it seems ineffective.