Seller has not contacted yet. How long should I wait...

I bought an item (auction) approximately 12 hours ago from a  member here who's currently has no transactions and no feedback. Seller has not contacted me yet regarding the transaction. I sent a message through Audiogon at time of purchase and also sent an email about 12 hours after the transaction. How long should I wait until I contact the staff here? Or what other steps are to be taken if they do not respond in a day or two?