I would scope the place out. But I don't remember ever seeing anyone that I was interested in....
There was a guy in my cong who was desperate to get married. He got it into his head that his soul mate would be found at the DA that was coming up. So off he went wearing his heart on his sleeve. He sat next to a family with a pioneer daughter who actually said 'hello' to him and he decided she was the one. He noted from her lapel card where abouts she was from and decided to hunt her down.
Every Sunday he would drive for 3 hours scouring the different congregations in her area until he found her. Evenutally a few months later he did. Then he rushed up to her and told her his story of trying to find her and being in love etc.
Strangely enough she didn't see this behaviour as odd at all. (Personally I would feel it was like being stalked). They are now married.