Where to find people for otakuthon?

For the last two years I had to go to otakuthon on my own. This year I finally convinced a buddy of mine to go, but a family member got sick and he ended up having to go back home to care for them.

I don't want to go alone again. So I would like to try to meet people beforehand that want to go or something like that, but I am not sure what to do for it. I don't really see anything in MeetUp.