Yes, we have begun to come to terms with the fact that it will always be a bit more difficult for me to meet someone. Our social circle is "tapped" so I will have to look into ways to expand it. I took a quick look at our metro area on Meetup and found two poly groups in the KC area.
As far as dating sites go, I know for a fact that POF has taken a strong, public stand against married men on their site. A few months ago, they sent out an e-mail stating that all profiles of married men were to be reviewed and if it was found that one was looking for any kind of non-platonic relationship it would be deleted. Their reasoning was that there were "so few woman looking for that kind of relationship" and that essentially married men were a nuisance. I, being quite open and frank about my status as the male half of an open marriage had my account deleted. All further attempts to establish a new account have also been deleted within 15 minutes even when taking care to avoid any kind of sexual references as outlined in their new TOS. Funny thing is that my wife's account in which she is also quite clear about her open relationship has never been touched. So evidently, it is OK for married, or otherwise committed, women to use their site to find men but not vice-versa.