Consider Listings Project, too (they might charge a fee, but it's vetted & way more reliable than Craigslist or something).

I've seen a few folks recommend it, but I want to echo Bergen-Lafayette. I'm a youngish woman and often get street harassed if I'm walking alone near the JSQ PATH, but Bergen-Lafayette (from Liberty State Park over to Monticello) is quieter, new businesses are taking up shop alongside some charming established ones, and the neighbors are really kind. Listings Project, an email listserv, occasionally has roommate posts (though I think they're usually downtown). Plus, you get access to a big park for some outdoor space.