Many of the Web sites listed below also have advice for job seekers.
Idealist is a website that lists non-for-profit jobs. It is a project of the non-profit organization Action Without Borders.
Hiring Squad is the Washington Post's Web site that gives both advice on getting a job (check out the tools and games), and lists jobs, concentrating on the DC metro area. This include federal and not-for-profits in the area.
New York Times Job Market concentrates on jobs in the New York City metro area.
Global Museum has many jobs listed.
USA jobs is the gateway for federal employment.
New York State Department of Civil Service is the gateway for NY jobs.
Higher Ed jobs has employment at all levels at colleges nationwide.
Local jobs in the Potsdam, Canton, and North Country can be found at North County This Week, St. Lawrence County One Stop Career Shop, Seaway Help Wanted, Penski, and Kelly Services. The local colleges also have career information on their websites, and SUNY Potsdam's Employment page has links to the other local colleges.
In Canada, two majors sources of jobs listings are at Monster.ca and the Ottawa Citizen's working.com (this site also has extensive job search advice). Most positions in federal and local government in Canada require both citizenship and residence in the local area; if you meet these requirements, jobs are listed at the Public Service Commission of Canada.