Freepik

http://www.freepik.com/

Freepik is an online search engine that you can use to search third-party websites for royalty free images and vectors.

You can either search for free images or vectors. As soon as you find the best image for your needs, you just need to click on the download button and Freepik will redirect you to the original website where you can download the image for free. Image sizes and resolutions differ as they come from varied sources on the web.

Photos.com

http://www.photos.com/

Photos.com is an online stock photography site where you can find tons of beautiful royalty free stock photos to utilize inside your creative projects.

All images are available in low, medium and high quality, different sizes and released under different licenses. Registration is requestes to purchase and download the stock photos.

Subscription plans start from $99.95/mo, and discounts are available.

Fotegrafik

http://www.fotegrafik.com/

Fotegrafik is an online stock photography repository where you can find tons of beautiful stock photos to enrich your creative projects on a budget.

All images are available in high-quality, in different sizes and are released under different types of licenses, royalty free included. Registration is mandatory to purchase photos.

Photographers are also welcome to contribute their own photos and monetize their image inventory.

Wylio

http://wylio.com/

Wylio is a web-based image search engine that you can use to find all images shared on the popular photo-sharing Flickr which are released under a Creative Commons iicense.

Once you have found the image you need, Wylio also generates a standard snippet of embed code that you can paste on your blog to display the image. The embed code is complete with attribution to the original author and source.

iClipart

http://www.iclipart.com/

iClipart is a royalty free clipart site with also a large section dedicated to royalty free photos and royalty free photo objects.

To purchase royalty free images from iClipart, you can either purchase individual images or pay for a monthly subscription (different plans are available depending on the kind of image you need) that allows you to download as many royalty free images you like. All images are available in high-resolution and in different sizes.