A good free tool from 123promotion listing all the available free and paid directpries with links to their submission pages and a system to allow you to register and record the progress you are making. Their listing shows various measures of the importance of each directory and the list contains over 140 directories that are FREE.
Firefox extension to make directory submissions a snap
We love this little Firefox extension called InFormEnter - it makes submitting to directories really easy. You can store all your site information such as URL, Title, Description, etc. into different profiles (short description, long description, different anchor text, etc), and then with a click of the mouse, have the info entered into a directory submission form. Get it at the Mozilla page.