LINKS TO FREE CLIP ART SITES:
Pixabay.com: (Toggle across the top to illustrations or use the search bar)
Freepik.com: (Pay attention to which of its resources are free and which are only available to premium subscribers. Tick the "free" box when you search. Most of the free images will need attribution before you publish it (giving credit to the artist that created it.)
Flaticon.com: (A crazy amount of icons! Part of the Freepik family, also needing attribution.)
Thenounproject.com: Over 2 million curated icons that you are free to use.
Pixabay.com: (Toggle across the top to illustrations or use the search bar)
Freepik.com: (Pay attention to which of its resources are free and which are only available to premium subscribers. Tick the "free" box when you search. Most of the free images will need attribution before you publish it (giving credit to the artist that created it.)
Flaticon.com: (A crazy amount of icons! Part of the Freepik family, also needing attribution.)
Thenounproject.com: Over 2 million curated icons that you are free to use.
Image File information from 99designs.com.