Children, hair, time, health, peace of mind. Lots of stuff that money cannot buy

Back to the original question. Google around for more information. There are also different levels of headhunters, low level ones eg. Kelly Services, mid-range like Robert Walters and high end ones like Korn Ferry. Where you go and what you do depends a lot on your networking and who you know. Many headhunters depend on referrals to get trusted candidates so network more!