There is a nice little tool to let you make eBooks that can be read on GB & GBA handhelds, but if you don't register it puts ads in and limits how big the bookes are. I want to register it but the owner's store just says "Shop closed". It's called BookReader, here is the website for it:
http://www.mqp.com/fun/gb_reg.htm

If anyone knows the author please send him my way - will pay $50 for it.

Thanks!