1. As a test, try to download a book citation from the Quick Search or Amazon.
2. You should see a small icon of a book near your browser bar. This appearance and location of this "capture icon" depends on your browser. See examples in images below. No "capture icon"? You probably did not install the browser connector correctly. Go back to Zotero.org to install; close and re-open your browser.
Chrome
Firefox
Safari