C-SPAN will cover the event live, beginning at about 6:30 pm ET, when guests arrive. MSNBC will also have a live stream. Note, that this isn't a White House event. It's an annual scholarship fundraiser put on by White House press.
Obama will speak. His speech at the dinner is usually funny. Last year he mocked birthers and Donald Trump. This year, he'll probably stick to GOP wannabes and republicans in general. He'll be followed by Jimmy Kimmel.
This year Zooey Deschanel, who's awesome, will be a guest of Bloomberg. Fox News invited Lindsay Lohan and Kim Kardashian. Of course. Chris Christie and David Axelrod will be at the same table, guests of ABC. See the guest list. Just a little Zooey (She & Him) for fun: