Wow ... All I can say is, I hear you on how frustrating it is. I went the OKCupid route myself and didn't have much luck (although I know some people have had good luck with OKC). And you've already met up with some of the local poly community in you're city, so it's not like I'd have much advice for you on that.
I would say, keep attending the events, don't give up on that, but it might take awhile, and really, if it has to do with dating, there's no guarantees (and you're right, it's even tougher for a poly person). You can't know what the future holds, so take comfort in what you have right here in the present.
Sometimes it's therapeutic just to make new friends. Which is why I say, don't give up on the poly events. Also, if you have other interests and there are local clubs for those, it's not a bad idea to get involved with those kinds of things. Maybe you'll just make some new friends and that's about it. But that's not all bad, and you just never know if a friendship sometime might go somewhere further.
They (sometimes) say that you never find anyone until you're not looking. I'm not sure that's a scientific truth, but I do know that life has a way of surprising us. So try not to get too discouraged, or stress yourself out by looking too hard. Be yourself, enjoy being yourself, and being with others.
That's about the only advice I can offer; sorry I don't got much better! I do want to welcome you to Polyamory.com however.
Regards and respects,
Love means never having to say, "Put down that meat cleaver!"