There was a time, a while back, when I played with creating images from stock photos. These were not from the expensive "royalty-free" collections containing high-quality, multi-megabyte images and costing hundreds of dollars for each CD. The ones that I worked with were more of the "65000 images for $50" variety. They contain a wide variety of images, and you never know what you're going to find.
The problem, of course, is that the images are tiny and of fairly low quality. But there are ways around that.
Here's one approach to creating an image from a tiny file. After cleaning the file up a little bit, I converted it to PostScript. In this form, the image consists of lines and shapes filled with color, rather than the pixels that it once contained. In PostScript, there is no concept of resolution. You can convert the image back to pixels for printing or other uses, and the image can have whatever resolution you want. One of the reasons for converting the image from PostScript back to a bitmap is that there are more tools for working with color in this form.
After converting the image to PostScript, I modified the lines to add the curves. Then I added a light grey/silver border around each shape. To finish off this version, I did some editing of the individual shapes and modified the color that filled certain areas. After that, the image was converted into a bitmap. I used a regular photo editing program to fix the brightness, color balance, and saturation to produce this final result.