Creating or finding good mockups to compliment your design work can be tedious. Luckily there are websites that provide you with free mockups, but again finding the right one can be hard. I have put together a list of websites where you can find mockups that will suit all of your needs.
Mockup World is an online service that offers designers and web developers free access to hundreds of ready to use mockups ranging from Apple Watch to Billboards.
Free Design Resources
300+ handpicked free mockups to make your presentations stand out Ranging from print mockups, apparel, packaging, screen, logo, and more.
GraphicBurger is a collection of premium quality design resources offered for free to the community. Curated by Raul Taciu.
Selective collection of free mockup resources, which can be used for presentations and showcases.
Pixeden offers a one-stop place for all the tools that a modern designer might need in their day-to-day routine. This includes mockups.
Freebiesbug offers a great collection of free PSD mockups to better showcase your apps and websites.
A large collection of resources for various platforms. You also have access to fonts, icons, scripts, and illustrations.
Original Mockups offers High-quality mockups for Photoshop that make your designs stand out. Also, check out their Mockupmator plugin for photoshop.