SEO Directories are beneficial to me, because I provide writing services for search engine optimization. It will be beneficial to you to get your website listed in directories that are related to the topic of your website.
Their Search It! tool combined with their forums make it beyond easy. You can try the tool by clicking on the link. If you have a pop-up blocker, be sure to hold down the Ctrl key before clicking on Search It! in the page that comes up.
The only other way I know of to find them is the good ole' Google way, by searching for them. That can take tons of time.

A website without traffic won't do you a bit of good. Concentrate on building traffic by populating your site with keyword content and getting incoming links to drive your website to the top of the search engines.
The main purpose of directory listings is to get incoming links. You may get some traffic from the listing, but that is not your goal. Don't be disappointed if you get listed in a directory and you don't get any traffic from it.
If you offer SEO services, you might benefit from being listed in the following directory...
seo directory quality selection of seo related resources.