Decided to just come out and ask since the search results aren't giving me much.
The free tiers on most of what I've tried are basically useless — you get just enough to see that real people are there, then hit a wall the second you try to actually message anyone.
I've tried a few different things already with mixed results. Some were complete time wasters, others were okay but nothing that really clicked.
Feel free to share whatever has worked for you, even if it's not the obvious answer.