Produce an ePub book using Adobe InDesign or any other ePUB creator suitable to you computer.
I know its possible to have an Apple account using Windoze PC,however - I just tried downloading iTunesProducer on a PC and its a .dmg for use with Macs only. So without a mac I don't know how you could deliver a book.
So your other options is to use an agency to manage your book(s) Apple have a list they recommend or if you search this forum there are others. A typical cost for one book is US$99.
Apple are rolling out new machines between now and September - so there will be used equipment available or reduced price old models from Apple stores and there other outlets.