At Boing Boing, Maggie Koerth-Baker points to and paraphrases none other than Stephen Hawking: "For the love of god, everybody just stay quiet. If we're lucky, they won't notice we're here." Hawking joins many others in taking the same position.
By all means, we should try to hear them. But not vice versa. Did Native Americans build signal fires on the shoreline in case anyone in huge ships was sailing by and wanted to exchange their transcendent philosophical ideas?
Perhaps the Fermi paradox is best explained by rational behavior of the organisms involved. And the ones that make noise aren't making it for long.