If you want well-known masters of photography, then here are two sites.

[Profotos][1] has a lot of narrative about the photographers, with links to photographs.

[Masters of Photography][2] has a lot of images, but the site is littered with pop-up ads, so may put you off


  [1]: http://www.profotos.com/education/referencedesk/masters/
  [2]: http://masters-of-photography.com/