If you must know, I kept trying periodically and somehow Ticketmaster showed 1 ticket available around 1:05pm, over 3 hours after it went on sale, and I snagged it! Pretty good spot, too. Row Q, main concourse near the stage. I must've searched for tickets about a hundred times. Sometimes persistence pays off.
And, yes, the Adele ticket prices on Craigslist and StubHub are insane!