Anyone know about the legality of posting book notes on a website?

there’s nothing wrong with posting notes about a book, and quotations are certainly allowed as long as you source them. if you were actually posting up huge sections of the book, that might be a problem, as it could potentially be seen as giving free, unsanctioned access to the book out to the public. but quoting someone is certainly not against the law. :)

I would say that you can post notes about a book. But, if you are quoting large portions of the book, in a manner that could be seen as infringement of any potential copyrights, you could be in trouble.

The above doesn’t apply to books in the public domain.

If you don’t want to directly post content of a book, you could link to it on Google Books and that way the content isn’t hosted on your site :)

You have nothing to worry about.

Even quoting large portions of a book shouldn’t be a problem. Students and professors write papers with extensive quotations and they don’t get in trouble. Bloggers write book reviews. Quoting a book for book notes, reviews, criticisms, etc., all fall under fair use jurisdiction. Do you think book reviewers, from NYT, Amazon or LibraryThing pay royalties to write about the books mentioned on their respective websites? They don’t, because our copyright laws consider those types of derivative works as fair use.

The only thing you need to make sure to do mention when you are quoting and where from. Plagiarism is a whole different matter…