Newsgroups can also be a good job source:
Note: Not all these newsgroups may be available with your ISP. Each of these newsgroups might not have activity at any one time.
Updated for 2017: Newsgroups were very effective in the early days of the Internet, before Job Search websites began to proliferate. They are used much less than in the early 2000s, but may still present a good resource for hiring and for jub-hunting.
HOWEVER, be on the lookout for "self employment" "Jobs at home", "books with lists of jobs", ant "Multi level marketing" or "network marketing" opportunities, ads, and emails on these un-polices newsgroups