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Like Musicspryte said, Google and search what you want for and do wallpaper size as an option. Theres also GettyImages and Corbis. You can get free low res comps but they are taken by proffesional photographers and are much better quality (subject, angle, ligthing, etc) that Google, IMO. You can also purchase a high res picture from them as well. Probably not 100% what you wanted but at least its an option :)
 
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