There are two popular theories about directory submissions (among many)

1. Submit to high PR directories only.
2. Submit to 'new directories' as well as high PR directories.

I subscribe to the second theory because doesn't matter what's the PR of the directory, your listing is normally on a PR0 or N/A page. New directories might turn paid (or might become link farms or dead) so you are in some paid directories if you submit to them when they are announced.

You can see 'new directories' on following lists:

www dot directorycritic dot com / free-directory-list.html?sort=date_added&pg=

or

www dot vmoptions dot com / directory-list.php

or

managedirectorysubmissions.fastreviews dot org / new_directories

Hope this helps

This is one of the best free listings of free web directories where you can submit you URL for free:
web-directories.ws

There are so many free directories these days. A couple years ago I released a web directory form filler extension for Firefox, which I had been selling until now. I finally decided to make it available free of charge to everyone to help with submission to all the directories. You can read more about it and download from the URL below. I ask only that if you want to mention it on your blog, that you link to the page on Gadget Advisor rather than hosting the actual file. If you need any help, don't hesitate to let me know. I hope you all enjoy using it!

Note: I don't have enough posts here for a live link yet. If someone wants to follow-up with a live link in reply so that it's more convenient for others to link, feel free to do so.

gadgetadvisor.com/computer-software/firefox-web-directory-form-filler-extension