It's getting to be fairly well known that you can submit your site to directories to get one-way, relevant links to your site.

Just go to Google and type "search engine friendly directories" into the search bar. You will get a huge number of directories.

You cannot realistically submit to all of them. So what do you do?

Go to each directory and note their page rank. To do this, download http://toolbar.google.com/. Then with each directory you visit, see their page rank or PR. The higher the PR, the more green you will see on the Google page rank bar. Essentially, if a site or page has a PR1 you will see 1/10th of the bar in green and so on, and the higher the PR the better the directory in that with a higher PR it will get listed in the SERPs (search engine results pages) more often.

Find the directories with the highest PR you can find. Then select the category and subcategory of your site. If your site is about golf, then the category might be sports and the subcategory might be golf. It will vary with the directory. If you see thousands of site links on the golf page, then forget that directory and move on to the next.

You see, you want to pick a directory with a high PR. But then, you want to put your link on a page that has less than 20 links.

Google also gives more weight to links on pages with fewer links. If your site's link is on a page with thousands of other website links, even if the directory has a high PR, your site will "share" with the other links will not do as well.

For example, the other day I found a directory with a PR5, which is respectable. My website is about fishing and so I clicked on Recreation and then Fishing. There were only 3 links on that page. This is good. And so I added my website.

Even though the fishing page was not ranked, because the index page of the directory had a PR5, I know that the search engines will be visiting that directory fairly often and follow the links to other pages. Finding a low competition link page will make my link more valuable when the search engines index the fishing page.

All of this will take time. You may put a link on directory page and not see any action for even several months. Do not be discouraged. The search engines work in inscrutable ways, but if you plant the seeds, they will sprout.