I have multiple lists....
In
Delicious Library I keep a list of every book I own, and every book that I have read and every book I want to read that is available as an ebook from the public library (so I don't accidentally buy a book that I can borrow).
In
Calibre, I keep all of the ebooks that I own, and I use the rating system to show which have been read.
On Amazon, I keep two wish lists; one for ebooks I want to read, and one for books that are not yet available as ebooks.