Looking for some placeholder images to use in your shop while you're setting things up? Feel free to grab any of the following, which are sourced from Pexels, Pixabay, Unsplash and other free stock sites. They are licensed under the Creative Commons Zero (CC0) license which means they are completely free to use for any legal purpose. You can always browse the image stock sites for the original high res images, or simply right click on any of the following to copy or save them to your drive.
Shopify has also created an excellent resource for photos and business ideas for your shop: Burst by Shopify - Free Photos for Entrepreneurs