Why not go to a scenario page and 'Seek Game'... what's the worst that can happen? :)
To look for a game, make sure you're logged in and select Seek Game from the scenario page.
Offering a game to the opponent will send that user an email with your email address attached. That player should then contact you and decide whether to accept or reject the challenge.To send a challenge to a game sought, challenge the player via the scenario screen.