Using product images in your app/site

Hi fellow IHers!

Does anyone have experience with building a product review site/aggregator or another digital product that would benefit from having product images? If yes, how did you obtain the product images? Are there any ready made databases or repositories? What legal issues if any did you have to navigate?

My context: One of the most highly requested features on lipcolourmatch.com is to have product images, but unfortunately I don't have the capacity to photograph thousands of products and am a bit wary of using photos from the brand's site, because I am not sure about the legalities surrounding this. Would appreciate any thoughts.