Quadrille - 9:29 am on Jun 30, 2007 (gmt 0)

It depends entirely on YOUR industry; that's why a Google search with YOUR keywords / phrase is so important.

Many niches have very high quality free directories, assembled with love and affection, and kept right up to date; others have just some sad portal set up by a B list site who just want a few adsense dollars. Some (eg real estate, travel), you'll find thousands of cr*p directories and you'll be amazingly lucky to find a single quality one.

Most are somewhere in between. But a specialised, quality niche directory will do what virtually no general directory will ever do - bring you direct referrals in good numbers.

You may be unlucky - but the search is well worth doing. And when you have done that, also search (if relevant) for local directories.