Searching for imageboards is hard, because there is no convinient list with imageboard. I mean, why would you want to visit something you don't like? It would bad for everyone, imageboard users, because they would be pissed off by your behavior, and you, because you don't really like the place.
This is why I've made an imageboard list, which allows you to describe common acitivity and things you would like to have on your board, and decribe activity and things you don't want to see on your imageboard.
Also, I've updated my imageboard list.
Now you can see all imageboards we have in the database.http://electroboard.ga
Consider adding your imageboard there. It is free.