Thanks for your support (at least that's how I recognize it
). It's a lot of work and computers were invented for one and only one purpose: to move that work from people to them.
In essence any datamodel about books that represents reality more or less has to take into consideration that there are numerous books (omnibus, collection etc.) that are reprints of collections of other (single story) books. Each of the originals has it's own data (exactly like the one story book). The collection, omnibus or whatever is just another book (with it's own data) but also referencing the part-books. Thus in terms of the datamodel, a simple book is a book containing one book (the story). This beeing the default seems to solve things (from a datamodel point of view).
Nevertheless I agree with Kovid that implementing this datamodel is not a simple matter; most certainly not in an existing program.