while it's easy to find people's accounts on Tumblr, it's easy to network fans, on LJ if you don't know people it's hard to find them

How odd. The exact opposite was true for me: I couldn't find anyone to follow except the few people I already knew - and most of my friends said they didn't even want to give it a try since they couldn't find anything there.
Of course with nobody actually active around here it's been no use either, but back when LJ was alive I had no problem finding people.