Haven't been there is years, but there always seemed to be a pool hall on every block. And gambling was available from peanuts on up.
No problem on pick-up games. If you bulldoze the existing players, runners go out to notify the better neighborhood shooters.
You'll also attract a lot of attention just being an American shooter.
You can either memorize the common pool terms (i.e., rack, cue ball, object ball, corner pocket, side pocket, rail, bank, 9 Ball, 8 Ball, One Pocket, etc.) or have a Chinese player give you a cheat sheet with translations (when gestures don't communicate).
Don't get distracted by the few players who want to use you as an English tutor - distracts your focus.