AFAIK you can't (at least not yet...) search for a user's photos, and they aren't indexed in any search engine. You have to click on the photos link on a user's

AFAIK you can't (at least not yet...) search for a user's photos, and they aren't indexed in any search engine. You have to click on the photos link on a user's profile to see the photos they're tagged in. (So you're pretty safe.) However, if they can view the photos of someone who has uploaded one of you or tagged you in one, they'll be able to find you in them eventually (by browsing through them, or if you're feeling really paranoid, they could automate the process and scrape through all of a user's photos' web pages to find your name tagged), but it'd be a lot of work.