I do have a large PDF document created based on 10 different .tex files. Im using Mac and I want to spell check these words such a way that I can get list of incorrect words (e.g., by using a shell command, or a tool). How can I do that?
One option is to use an editor that has a build-in spell checker. Latexian will check your spelling while ignoring formatting, however it's not a free app ($10).
How to perform advanced spell checking of latex documents? describes how you can strip the formatting for spell checking in Text Edit, for a free solution.