Do any exist? If so, please point me to them.
The Math & Science Tutorials forum here got a thread https://www.physicsforums.com/showthread.php?t=174685
Check those. In fact there's so much books, that it is difficult to find which are good ones.
Ahh thanks. For some reason I never thought of looking in that forum.
I assume its legal, don't see how it couldn't be so long as you're not reselling them, but do some searches in google like:
Quantum Mechanics filetype:pdf
Quantum Physics filetype:pdf
it results in pdf's online, quite a few of them books, or books in progress, mostly from professors in universities.
Separate names with a comma.