Sources for art, human figures, graphics...

I know that the word "clip art" has a bad ring to it.  

However, having fun ideas about making interesting trainings using StoryLine -- and considering doing so without much graphic designer assistance -- has me wondering about how to get a fair amount of graphic assets (pens, computers, trees, chairs, chalkboards, ... all the props that will help make a little narrative.)

And, though I know that I can buy the additional set of photographic characters from Articulate, I have to admit I'm a little interested to hear if there are other sources for human characters too.

Where does one go for this universe of graphics?

by the way, if someone knows of a quick, ad-hoc way of getting a few graphic elements designed without setting up a big contract with a graphic designer, that would be an interesting option too.

THANKS!

eric