1. SUPERFAMOUS Site: http://superfamous.com/
  2. GRATISOGRAPHY Site: http://www.gratisography.com/
  3. LITTLE VISUALS Site: http://littlevisuals.co/
  4. UNSPLASH Site: https://unsplash.com/
  5. LIFE OF PIX Site: http://www.lifeofpix.com/
  6. MMT Site: http://mmtstock.com/
  7. STARTUP STOCK Site: http://startupstockphotos.com/
  8. PEXELS Site: https://www.pexels.com/
  9. MAGDELEINE Site: http://magdeleine.co/
  10. JAY MANTRI Site: http://jaymantri.com/
  11. STOCK SNAP Site: https://stocksnap.io/
  12. RE:SPLASHED Site: http://www.resplashed.com/
  13. PICOGRAPHY Site: http://picography.co/
  14. ISO REPUBLIC Site: http://isorepublic.com/
  15. STOKPIC Site: http://stokpic.com/
  16. WEFUNCTION Site: http://wefunction.com/
  17. RAUMROT Site: http://raumrot.com/
  18. FOODIESFEED Site: https://foodiesfeed.com/
  19. BUCKETLISTLY Site: http://photos.bucketlistly.com/
  20. CUPCAKE Site: http://cupcake.nilssonlee.se/
  21. GETREFE Site: http://getrefe.tumblr.com/
  22. SPLITSHIRE Site: https://www.splitshire.com/

Fique atento as licenças pertinentes e a resolução na hora de escolher. E aproveitem!