Nicholas has found a groupon for fencing instruction in Brooklyn.
They seem to focus on epee, and I'm not sure they will have any classes for adults in foil. But the groupon is for a class and a 20 min. individual lesson (or 2 of each). At that price, it's worth it to just get the individual lessons.
I chose the $29 option. Let me know if you want to schedule lessons on the same day.