Microsoft’s Bing image search offer filter search based type and sizes. “Go to Bing and type in [Seattle], click on images, then mouse over an image you like and you will see a link that says “Find more sizes”. Click on it. You’ll get a page listing where all of the “same” images appear online (with different format, resolution, or with minor editing). You’ll also able to see other ways this image has been used (mockups, editing, cropping, framing, etc). This’ll be helpful for many instances where you need exactly right resolution, file size or type for a certain project.