i checked some from 3dsk. I think it is impossible to use any of them without editing in pohotoshop first.
If you intend to use photo ref for texturing you are going to have to use PS or some other photo editing app to create the texture, if you are expecting to just use one picture for a texture then i am afraid it's not going to be very successful as trying to line up an image with a UV snapshot simply will not be possible without bad distortion.
The technique would require you to build up your complete texture using parts of images taken from side,front and other views, this is where good photography comes in because you need the lighting to be even and the same for all images or else you will have a lot of color correcting and matching to do. 3dsk is ideal because they take sets of images for exactly that purpose.
2 x Modeling Challenge Winner