There is information in this wiki:
Skyrim: Dawnguard
Also here is a walkthrough with instructions on how to start the quests:
Skyrim Dawnguard Walktthrough
which video game prank did you like best?
(theres list of all the pranks here: Video Game April Fools Jokes 2012 )
I think the best was the Assassin's Creed Kinect one
some useful Mass Effect 3 resources:
Mass Effect 3 Walkthrough
Story Recap from ME1 and ME2 (Video)
and if you don't mind spoilers, the following guide lists all the endings:
Mass Effect 3 List of all Endings