Designer's need photography. But the choice of what photos to use in a design can either make or break a design. There are some cheap stock photography agencies out there where you can find cheap stock photography that is not widely used.
Istockphoto.com offers thousands of stock photos from photographers around the globe. Their rates are extremely cheap when compared to other stock photography sites. You can get a small image for the web for a dollar. Larger images for print cost 3 dollars. They also offer vector images that can be opened with adobe illustrator or macromedia freehand and manipulated from 1 – 5 dollars. This is dirt cheap and probably why this site has gotten so much attention since it's inception.
When you are surfing photos at Istockphoto pay attention to the times a photo has been downloaded. Their site tells you how many downloads each photo or image has received. This is an indicator that the image you are viewing is either super popular or is not. Less downloaded images are less likely to be seen as duplicates on the web or in print. Less popular images of course might no suite your design but are less likely to be seen as an over used image.
If you want to use a popular photo but still look original try cropping the image. Many times people won't be able to immediately tell that they have seen a photo before if it is changed up a bit. A simple reversal of the image might be all it takes. Try reversing the image horizontally or even replacing colors within the image. This can be easily done in Photoshop.
Fotalia.com is another stock photography site that offers photos not found on Istockphoto.com. Their site offers larger previews of photos so you can see clearly what you would get. I have found great photos that are not offered on Istockphoto's site. They offer either web or print use for $1 dollar and $2 dollars respectively. I suggest checking out their site if you haven't found that perfect image on Istockphoto's site.