Is there a in detailed iTunes manual ?

I would like a detailed iTunes 'Operating Manual', either on line or in writing.
Is such a thing available ?
I find the 'question' and 'answer' instruction thing very unsatisfactory !!
I would like a 'step by step' guide through iTunes, describing all the features and detailing all the menus, buttons and options!!
Can anyone help, and point me in the right direction??