Kbblender

If you're not at the direct link to your image you need to acquire it by opening the source of the image. Many times you won't receive a link to the fully downloaded image and instead to the page it's hosted on unless you open it in a new tab and copy the url atop.

Here's a quick example as to what I mean.

http://fc09.deviantart.net/fs70/f/2013/191/9/1/new_canvas_by_accellerant-d6cx3tk.png

I uploaded my image to DeviantArt > Right Click...

* Deviant Art > Right Click > Open Image In New Tab > Copy URL up top.

The biggest giveaway is that the end of the url ends in the file format of your image. Yours will most likely either be .jpg or .png.

I forgot to clarify, right click the image itself