I really look forward to a report from you on your adventure. As everyone else has told you, observe from the back for a while or hook up with an experienced guy from this site. I would suggest two things: have no preconceived ideas, a guy on their website might appeal to you but once you are there, you never know which dancers will "click" with you. This happens while they move about the room and chat - it also happens during the dance. The second thing is take guys for a test drive and don't be afraid to end the dance early, after one song - and leave the door open for more later. Finally, I have found as as the dance goes on, the guy will become more comfortable with you and you with him - and sometimes, that's when the magic can happen.
Have fun!