There are lots of websites that you can easily find free images to use without having to give attribution, I have put together a list to make life a little easier. If you have any other suggestions please give us the link in the comment section.
http://photopin.com/ – free photos for bloggers
https://unsplash.com/ very odd place to find free photos under the creative commons act they only release 10 new photos a day, they are all top quality.
Gratisography offers free high-resolution pictures you can use on your personal and commercial projects. New awesome pictures are added weekly and are free of copyright restrictions. All pictures are captured by Ryan McGuire of Bells Design.
Life of Pix is a resource created by the LEEROY creative agency offering free high-resolution photos with no copyright restrictions. New pictures are added weekly. I personally love the images this site has, amazing work!
http://freestocks.org/ Freestock offers a wide range of high quality photos all released under Creative Commons CC0.
http://snapwiresnaps.tumblr.com/ Get 7 free photos every 7 days. Photos are public domain and free from copyright restrictions, stunning selection of works!
http://nos.twnsnd.co/ old pictures with no known copyright that can be used freely, a lot of historical pictures such as the beatles and old factories. Incredible