In searching for images for a current project I stumbled on indisain, a royalty free site that offers all images free of charge.
You do need to register in order to login and download images (without a watermark). I found the variety good, but the image size varied from usable (1280px wide) to unusable (100px wide). Images are categorized, but limited search capabilities with categories. And some categories had more images than others, such as the landscapes category with 72 pages of images.
If you need another image resource, you can check out indisain here.
– Troy @ TLC