Just created a doujin group just now. It's open to the public so anyone can share whatever they want as long as it's doujin related. It'll probably contain a lot of music discussions since this site is mostly about VGM, but anyone that's into the other aspects of doujins is free to express about it. Post your favorite albums, news of upcoming events, and etc.
http://vgmdb.net/forums/group.php