I understand your approach. I don't think being poly means you have to have multiple partners. For me what matters more is the freedom and openness.
I'm using OKCupid, but not like "desperately" looking. I'm pretty casual and don't care much about the result. I try to make friends first, then let things develop naturally. Even if nothing romantic happens in the end, it's still good to have more friends.
Ideally I also prefer developing relationships with people encountered in daily life, but the probability of meeting poly-minded people in real life is very low. Well, depends on where you live and what you do, I guess.