I joined Powell books for newsletters and updates on discounted books. Plus everyday, if you write a review, and they pick your book you reviewed, you have to check the page everyday but if they pick the book you reviewed, you have a certain amount of time to contact them and I believe the prize is a $20.00 gift certificate.
But I found out they do something else.
They are located in Oregon. (I told you I am going to post events from all across the country) They have a lot of events each week, even ones for the children. Click here for upcoming events.
And if you sign up for their newsletter, you are entered into a contest for a $100.00 gift certificate.
I have not evaluated their prices compared to Amazon and other places yet but it seems like a good site.