Following are few resources for downloading wallpapers for your iPad.
1. iPadwalls – where you can download HD wallpapers in different categories.
2. iPad Wallpapers – your source for the best iPad wallpapers.
3. Crackphone – Collection of free iPad wallpapers in 1024×1024 resolutions.
Hope you will get the right wallpaper you are looking for your iPad from the above list.