The requirements are pretty simple. You must participate in the read-a-thon. (You need to do at least one update, participate in at least one mini challenge, and post a read-a-thon wrap up post telling us what you read)
There is a form to fill out at Reading Angel to be eligible for the giveaways. You can also sign up there.
I think it sounds like fun. I hope to read at least a book a day. Come join me!