Here’s something I do in my research sometimes when I don’t own the books I’m looking into:
- If the book has a preview of relevant passages in Google Books …
- I take a screenshot of the passage;
- Open the screenshot in Preview;
- Export as PDF;
- Open in PDFpen to OCR it;
- Copy and paste the passage into my document.
When I’m working with many such passages I save them into a single folder, and then use an Automator workflow to process them all (though I still have to copy and paste individually).
There may be a more elegant way to do this, and if so, please let me know on Twitter. (For instance, I know Evernote will automatically OCR your images if you have a Premium account, but I like to own my data.)