Nos sites abaixo você encontra imagens de alta resolução para download de graça com direito a uso comercial. ;)
- https://unsplash.com/
- http://www.gratisography.com/
- https://www.splitshire.com/
- http://getrefe.tumblr.com/
- http://cupcake.nilssonlee.se/
- http://photos.bucketlistly.com/
- https://foodiesfeed.com/
- http://raumrot.com/
- http://wefunction.com/category/free-photos/
- http://stokpic.com/
- http://picography.co/
- http://www.resplashed.com/
- https://stocksnap.io/
- http://jaymantri.com/
- http://magdeleine.co/
- https://www.pexels.com/
- http://mmtstock.com/
- http://startupstockphotos.com/
- http://www.lifeofpix.com/
- http://images.superfamous.com/