Little do many people know, you can't just use any images off the internet in your blog posts. Not only is this ethically incorrect but you could leave yourself open to copyright infringement.
Explaining Creative Commons and using images in blog posts
Wanting to make this process clear to my students, I typed up a document explaining copyright, copyright infringement and Creative Commons while also offering step-by-step instructions on how to use FlickrCC to upload and attribute images in blog posts.
Flickr currently hosts more than 75 million images that are licensed under a Creative Commons license. Depending on the license, you may use the images on your webpage, or make changes to it. There are many things to check. With ImageCodr.org, there is no need to do all this manually, you simply enter in the URL of the picture page (as seen in your browser) you are interested in and ImageCodr.org will generate the ready to use HTML code. It will also display a brief and easy license summary, so you don't get in legal trouble because you missed something.
From this page in Flickr you can search Creative Commons images that have only requested an attribution for their use. The 100 most recent images that have been licensed like this are shown, but there is a search field.
This is one of the coolest sites. Select the colors you want, up to 10, and it will search Flickr for images with those colors. It doesn't filter by creative commons though, but a great way to find images that will match your website color scheme.