Although search engines such as Google will eventually pick you up with their search engine spiders, it doesn't hurt to submit your site to them. With directories, however, you must submit your site to be included because they have no automatic "website finding" software. There are both paid for directories and free directories. In both cases, this is the process you should follow to submit to directories:
1. Find the category which most closely matches the website.If several or
more categories closely match the website topic, choose the one that has the
highest PageRank. (You can view PageRank by downloading the Google Toolbar at http://www.toolbar.google.com/.)
2. Read the directory submissions guidelines carefully and follow them exactly.
3. Register your website.
4. WRITE IT DOWN. Write the directory you submitted to and the DATE. Don't assume you'll remember everywhere you submitted your website, because you won't. And because directories don't like people who submit the same site more than once and fill up their queues, you don't want to be submitting to the same directory again and again. Plus, if you don't get in somewhere you will want to go back and check in 6 months to a year and resubmit.
Recommended Free Directories
Recommended Paid Directories
Topic Specific Directories
Find as many directories as possible that deal with your website's topic specifically and submit. You can find these types of directories by search for: keyword add url