I've found the following sites to be useful places to keep an up to date thread of my work. I used to keep a regular thread on each board that I updated every time I finished a new piece that I could show off. This approach pulled in a consistent flow of small publishers and private commissions. If anyone has any other locations that they have used successfully then please post them here:

ENWorld Art and Cartography Gallery:
http://www.enworld.org/forum/art-gal...ures-painting/

RPG.net Freelancing forum - note this is also a good place to find the odd freelance job:
http://forum.rpg.net/forumdisplay.php?f=12

The Forge - note the no images rule and the policy against bumping your thread!
http://www.indie-rpgs.com/forum/index.php?board=29.0

These have been the consistently useful sites. I'd also suggest the following sites as useful places to post work:

Wizards Social Networking Site:
http://community.wizards.com/

RPTools:
http://forums.rptools.net/index.php

Fantasy Grounds:
http://www.fantasygrounds.com/community/

Goodman Games Forum:
http://www.goodman-games.com/forums/...82b393599a9f95

Four Ugly Monsters:
http://www.fouruglymonsters.com/community/

And then there are the general purpose art sites that it can't hurt having a gallery on (though I've never got a job from one of these sites yet):

Deviantart:
http://www.deviantart.com/

Conceptart:
http://www.conceptart.org/

CGHub:
http://www.cghub.com/

That's all that I can think of just now. Post any more that you've got!