It takes a lot of courage to make the first contact for a lot of people. There are many couples where one partner wants a more than the other and takes some time to convince the other to try swinging. There are lots of males on personals sites but many couples are not looking single males. Some on these sites take years to get past just chatting to others. There are some that like to meet and never get past that.
If you want to start go to a club or party where there are some experienced people and start chatting, its the best way. Its not as embarassing as it seems. Everyone is there for the same thing.