You can do polygons on har.com map search, their new map search with neighborhood boundaries is very nice too. Given the existence and utility of HAR, I've had a hard time justifying using zillow/trulia when searching. Heck, both times in recent years I've bought a house, I set up a saved search in HAR and my partner and I would browse listings at night. Effectively, all our agents had to do during the showing process was schedule visits to our top properties.