Today Beroeps Organisatie Kunstenaars (www.boknet.nl) wrote about the Art Drawing Center. They are one of the first. We are very happy with there post.
BOK has a lot to offer. At their website for example you find a Bulletin Board, News, Art Supplies, Memberpages, Discounts, etc. Every professional artist should apply for there newsletter I think.
Interested? Go here to register yourself.