Hi and welcome to MR!
I still own a Palm Treo 650, although I am not using it as a PA since I got my touch, and sice I got my first dedicated ebook reader, some years ago. It is a lovely machine. It still has the best calendar ever.
To make my own books, from whatever source, I used
eReader Studio, that is still supported by eReader.com. I do not have it anymore on my current PC so i could not tell you exactly how it handles metadata. But it did as I could navigate through my collection quite easily. Let me know, will you? Just out of curiosity.