Hey Gleemonex, welcome to the Mead Hall!

to answer your question, there is not much user created art here in the MH, however this is the place that you are able to post(the place it is meant for, anyway) it if you wished.

A number of screensht contests were held back in the day, and links to a number of them can be found here, here, and here.

Dimeolas also posted a number of his artworks here, most seem lost to time. I did manage to find one, however. hope that helped.