MARTHA'S VINEYARD, MACiting its 80-piece orchestra and real silver place settings, several of the 500 guests at Saturday's wedding of Boston socialite Elizabeth Kessler and investment banker Peter Graham emerged from the affair dazed and disoriented, sources told reporters. 'I've never seen anything like this,' said Beth Risser, tightly clasping to her chest the commemorative wedding iPod preloaded with the bride and groom's favorite songs while she waited for the valet to deliver her 1996 Mazda. 'There were swans everywhere, 12 videographers, and about $800 worth of candles at my table alone. And was that Henry Kissinger next to the raw oyster bar?' While many of the attendees were bewildered by the spectacle they had witnessed, at least 6 percent of the guests left the wedding worried that the Kesslers had fallen on hard times. 