Check out these three sites below for FREE images that you can use in your signage, printing and digital marketing campaigns.
Free (do whatever you want) high-resolution photos. 10 every 10 days.
These photos are AWESOME!
Over 470,000 free photos, vectors and art illustrations.
This site looks and feels a lot like Shutterstock (a pay-for-use site) but its currently completely free and most images can be used with no need to credit the contributor.
Clipart for your needs in 2015. Highest quality, free for commercial and non-commercial use.