Where would you find movie stills that qualify for uploading?

Reading the rules within the "Add" page, procuring quality movie still may be difficult in finding. Are there any common areas where I should look to find suitable stills? Is IMDB solely the source? If so, how do you extract the photos from their database?

IMDB is one of the many sources you can find online. The press sites of studios is another great source. Some press sites are open to the public and others are closed to members of the press. You can also find hundreds of different databases for film/tv and fan sites (please note: only official watermarks are allowed - some fan sites mark all their images with their own watermark). If you find a good quality still from a Google image search that is not currently found here at MSDB that is also an acceptable source. Honestly, the whole internet is full of different sources to pick from. Part of the fun to me is hunting down images to upload. Happy hunting!