We just wrote a blog post about this at work (of course, we were looking at it from the other side). We referenced this article/survey on recruiting. Specifically, you may be interested in this:

“For candidate quality, respondents rated social networks significantly higher than job boards who landed in last place; while referrals were the most highly rated for quality.”

So you might find using LinkedIn or renewing internal interest in whatever referral system you have to be the best route.

My son did vey well finding a high-level programming job on monster.com. He got several interviews. Presumably, many employers use the site.

I have had good luck with craigslist.

In the current economic climate, to keep down the number of applications, you would best go through an agency, and pay them to do the selections for you. Manpower, Kelly Services, and Volt are probably the best known ones.

When you place a job opening online you have no way to limit the number of applicants, other than have the messages sent through a middle person who is paid to screen them.

If it is over $100K www.theladders.com