If you want to use an agent or consulting firm to get interviews at multiple companies you are probably better off finding a truly talented and connected recruiter -- they do exist. Ask everyone you know, including hiring managers, for referrals to good recruiters and see which names keep coming up.
Some companies don't use recruiters or consulting firms, they do their own hiring. If you've identified one or a few companies you really want to work for the best way to get interviewed is to know someone who works there.
What you say does fit with my intuition. If I wanted to start looking for a job now I'd talk to the folks in my network at various startups / the Googles or Facebooks of the world.
However, it does make sense that a connected recruiter would help with looking for opportunities outside of that sphere as well. The suggestion to ask for referrals to good recruiters and sort by frequency is a good one. I'll keep it in mind for the next time I start job hunting.
Thanks again!
And that's gameable with a bit of effort.
Seen in this light, the comments from Chris Fry and Sam Altman make sense. If you're looking for employment, have a very good resume and a good network you might not need an agent. However, they don't seem to be considering the case of freelancers who need to spend a large amount of time finding clients.
Given that I haven't worked as a freelancer this is something I know little to nothing about. Hence the question.
Cheers and all the best with your work!