We recently posted a job opening on craigslist.com for the first time. It cost $25, and let us target the Dallas market and industry. But beyond that it was basically a listing of all jobs in that region and industry. Our first resume arrived within 6 minutes, and about 10 days later they are still trickling in, total so far - over 200 applicants.
The next time we post a job opening however, there are a few things I would add to the notice, and if you ever use this service you might want to include it too.
1) No Attachments. In this day of computer viruses, have people cut and paste their resumes to their email.
2) Specify years of experience needed, several applicants were hoping to break into the business.
3) Discourage pictures, they enlarge the data file and can cause problems. Concentrate on the qualifications they offer on their resume.
4) Assure anonymity - although I had the impression that many applicants were hesitant to send their information in case they were sending it to the place they currently worked. That having been said, I don't think any of them were currently working for us, we have a pretty stable family.
We did notice a large number of applicants were either currently living in or recently transplanted from Las Vegas. And we also noticed a large pool of very qualified people out looking for work right now.