Images

I want to make submissions but i want to upload pictures for my concepts so is it acceptable to obtain images from other websites or do they have to be original??

Image upload best practices

Do not submit images with watermarks! Submit high rez images under 1 meg in size whenever possible.

• Images can include box art, screenshots, concept art, fan art, and more. When uploading images, we strongly encourage users to either associate their images with an appropriate gallery, or create a new gallery when necessary.
• Avoid adding images tagged or watermarked with other sites' URLs.
• No nudity or nudity related fan art on the site. The exception is for nudity that is IN-GAME in the store bought version of the game.

I'm pretty sure it's okay to take from sites.  You can't really make concept art and official screenshots your own like writing articles can you?

as long as its not watermarked basically its fine