Greenhills North is the one with Club Filipino along its outside perimeter. It is the one bounded by Ortigas Ave, Santolan, Annapolis and Club Filipino(?) St.
There is a subdivision gate along Ortigas at Madison and another right beside Club Filipino. Sorry I am not sure which gate you have to take if you do not have the subdivision sticker although my guess would be Madison. If so, from Wilson St. going to the Shopping Center, you turn left on Ortigas. Go straight till you see the overpass bridge. The intersection immediately following that is Madison. Turn right to the subdivision gate.