Like music, images are copyrighted. Permission must be granted by the artist or photographer before you can use them. This goes for commercial and non-commercial use.
If you’re looking for an image for a book cover, you want to find one that is royalty-free. It needs to be clean with a high resolution. (300 dpi)
There are many site out there with complete free images, but there’s a downside - many also have spyware.
If you’re looking for images, it’s better to stick with trusted sites that sell images:
Big Stock Photo
There is always a chance someone else has used the image, so do a Google search to see where else it appears.
Best case scenario is to hire an artist or photographer to create a cover from scratch. Not the cheapest, but certainly the best!
I’ve been a professional photographer for 23 years now and I’ve considered offering some of my photos for sale. (Since diversity seems to be my middle name!) They would of course be royalty-free and reasonable. If I decide to go this route, I’ll let you know.
Any other good sites for images? Would you buy direct from the photographer?
And your inspirational photo of the day: