Hi! I have an iPad and there are two downloadable video tutorials at the App Store specifically for the D5100. I got my D5100 four weeks ago and coming from an Olympus rig I needed to know about all of the bells and whistles of the D5100. They are $25 each and one actually has a test at the end of the tutorial to see if you were able to pickup the pointers of the video. In addition, I think there is a book D5100 for Dummies. Hope this helps, but the videos are the best since they are actually showing you how to navigate the cameras capabilities.
Happy Holidays!