To avoid using someone else's copyright protected images you aren't allowed to use for commercial or even personal use, Google Advanced Image Search has got you covered.
An awesome tutorial suitable for Photoshop beginners and intermediates where we create a cool looking gas planet from scratch, by applying a couple of rendering functions and a few tricks.
Camera images usually contain additional description about camera settings and scene information of the the picture taken. By using EXIF, you can view this data online.