Amazon has the VIZIO E470i-A0 47-inch 1080p 120Hz LED Smart HDTV for only $538 + Free Shipping. This TV qualifies for their Low Price Guarantee. (Find a lower price in 14 days of purchase and they'll refund the difference.)

This is a highly rated TV, and the free shipping and potential tax savings (depending on what state you live in) mean you'll probably not find this TV at a lower price.