The "Download Now" link directs you to the iTunes App Store, where you must continue the download process. You must have iTunes installed in order to open the link, and you must have an active iTunes account to download the application. This download may not be available in some countries.
From Addison Publishing:
55 Awesome Shelves that you can save as Wallpaper.Many different styles from Elegant to Hippie choose the shelf that best reflects your personality or mood.App is simple and easy to use:1. You can choose which shelf image you like by swiping Right or Left going to the next image. You can also choose images using the Roll View on the Top right hand corner.2. Once you have chosen the right image you simply press the "Save" Button.3. Retrieve the wall paper from your Photo'sA. Open SettingsB. Wallpaper > Camera RollC. Select Saved WallpapersD. Set on Home Screen