Having helped lots of people get jobs in the non-profit sector, I've found it's important to identify what you're looking for (I use a "must have" list) as well as what your "core value proposition" is, to use a marketing term. When you know what you want to do and what you have to offer to an employer, it's easier to sort through the various postings. You can read more about the "must have" list; resume building to highlight your distinct talents, skills and experience; and cover letters elsewhere in this blog.
As far as where to look, Idealist.com has a lot of listings; be aware that you'll get different results when you put in different search criteria. To cast the widest net, just say "NY" for state and city, and hit "enter." There will be a lot of listings, but just slog through. Philanthropy News Digest (PND.org) also has job listings. I have a more complete list of sites at my blog www.growhappycoach.blogspot.com.
Obviously, networking is the most effective way to find a job, and you are starting with a great source - the Smith group on LinkedIn. If there are specific organizations you've targeted, see if you can find a Smithie working there. When I was at City Harvest, I often met with recent Smith grads to help them on their way and I think you'll find a lot of receptivity. Again, it will help if you know fairly specifically what you want to do and what you have to offer. It makes it easier for someone to respond affirmatively.
Another hint: ask for 20 minutes of someone's time. It's hard for anyone to say no to 20 minutes. Seeing someone in person is preferable, but take telephone help if that's all you can get. The most successful networking meeting results in you getting at least one additional person to whom you can talk, and permission to use the person's name when you make the contact.
A FORGOTTEN GREAT PASSAGE FROM KEROUAC
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