I can speak with some authority on this new area. My latest book - an e-book - was released internationally by Harper Collins last month. It is the first of two volumes of Australian folk songs from convict ballads through to songs about Australian 'Romance' (no sheep involved. The present volumes offer music notation, videos, soundbites for every song plus, where available, the original collected recording (this is amazing)and was developed for iPad via iBook (you will find it as 'Australia: Its Folk Songs & Bush Ballads' or my name. Harper Collins have told me that Amazon is working fast to get their new Kindle (out this year) designed to feature music, video etc - it will do everything for e-books that iPad/iBook can - and, knowing KIndle, it will be comparatively cheaper. That said, I am loving my new iPad! I have Engtina and an autoharp app on it and can happily 'play' my english concertina when traveling. The world is changing rapidly and you might as well hop on.