great tips, vr. thank you.
you can also use the epub generator at our very own hadrien's feedbooks.com. hadrien is currently working on a wysiwyg interface, which will make things really easy even for someone who doesn't have much experience. and it will generate clean, valid code and beautiful texts, in the new standard format. which is one step closer to eliminating the tower of e-babel. epub can be read natively on the sony 505 already, soon on the cybook, and more devices coming soon. and it can easily be converted into any other format like mobipocket (.mobi or .prc) if you can't read it on your device.
hadrien will make a tutorial and a video as soon as the interface is done, to explain exactly how to proceed.
if you want to start learning how to make ebooks, i recommend you learn how to make epub.