I’ve taken a small personal project public:
Public Calendar of SF/F/H Conventions with Art Shows or Artist Alleys
It’s pretty Western North America-centric right now (i.e. my mail-in radius 
but I’m starting to add outside my own range; I hope this will be helpful. If you would like your convention added, just e-mail me the URL for more information (and make sure there is at least a “coming soon!” page for your conventions Art Show or Artist Alley!)
This was inspired by the fabulous calendar that Christy Nicolas (“Green Dragon”) used to maintain for the SFFHs_ArtShows mailing list.
