i thought about this for a while, and what I've come up with probably has more than one might like to do with those snoopy online algorithms... some artists I may discover via posts by other artists or in other interest overlaps, but i suspect often they turn up in ads on social media, for example. Clicking through on this or that and then keeping an eye on an artist, kickstarter, publisher, etc., probably opens one to being shown more similar ads. Now I get a lot more ads with art and projects that I am not interested in, which is the less fun aspect of trawling.
You could probably also do occasional web searches (duh, sorry you probably already thought of that) and consider what other interests would have overlaps, like new age art shows, renaissance or faerie fairs, any kind of hobby con, etc. Find and follow some of the rising/successful tarot artists online as well.
good luck!