...do you usually submit to? What's your strategy in general? Just to have an idea, or is it all about 'forever submitting'?
As many as possible, though I find it a mind numbingly boring task so I never seem to find the time to sit down and do directory submissions, and when I do I can manage about 5 or 6 at a time before *remembering* something more important to do.
You don't need to submit to whatever directories. But instead, you can actually select high acceptance ratio directories from here and start submitting. For me directory submission is first part of off site seo. With in a week your new site will be indexed and ready to do more offsite seo using link exchange, article submissions etc.