Did you ever wonder exactly what you need to look for when you are buying your Lulav and Esrog? What are the conditions that make it valid and invalid? A wonderful organization called Torah Live has put together an excellent video - short and to the point - that will take the mystery out of the process.
You can see it by clicking on the following link: http://www.torahlive.co.il/arba_minim
You'll need Flash to watch the video. Click here to get it: http://get.adobe.com/flashplayer/