Register for a Burner profile on the main Burning Man site
, and enter STEP (Secure Ticket Exchange Program), which is open until July 31st. If you don't get a ticket through STEP, the OMG Sale starts at the beginning of August, with another 1,000 tickets going on sale - make sure you register for that when it opens, and the tickets go on sale on Aug 7th at 12noon PDT - you must be registered for the sale to buy tickets!
Both STEP & OMG are will-call only tickets, and are sold through BMan so you don't have to worry if they're fake or not. Plus, the after-market will be heating up a lot around the beginning of Aug, as people realize their plans aren't going to happen this year for whatever reason, so you should be fine.If you want to go through a third party, do not pay more than face value + shipping ($380 +shipping, basically) - you will regret it.