You may have heard that search engines allow you to submit your website to them. That might sound like a great idea but it is actually a bad idea. Why? Because submitting to search engines means that eventually the search engines will visit your website and their is no promise they will even include it in their index and doubtful you will ever rank well.
The alternative to submitting your site to search engines is developing inbound links from external websites. When the search engines visit those websites they will follow the links leading to your site (which is what they have stated many times how they prefer to discover new content). This process will make sure your content is indexed and most importantly that you have a good chance to rank in the search engines since ranking is based mostly on the quantity and quality of links.
Submitting to search engines is simply no longer needed. What is needed is link development and link development will do the same thing as submitting your site and a whole lot more.
There is one exception to this rule. If you have had your website significantly penalized or banned, then you should submit a re-inclusion request. This is how you say sorry, I stopped doing what the search engines don't like and I promise to never break the rules again. Based on how believable your re-inclusion request is, will determine if the search engines unban you.