It's believed by almost every one that if you haven't submitted your website then it is not possible to reach to your users. But this is not true the search engine submission doesn't need any special skill or research. Your websites can be listed in the search engines without submitting. Ironically, search engines do index your site without submitting it to them. Search engines use some special spiders and many other tools which continuously look for fresh websites. If you have exchange linked to any websites which is already in list then you are listed automatically. Search engines go inside to your websites with a click on that link which is visible to that side. Hence pick out any myth regarding the submission and don't be afraid of it.
It is totally myth spread in the market that you have to list in the thousand of the search engines for achieving the good rank. It is also widely marketed by many SEO firms. Never trust in such offers. You can achieve the result by posting in the few popular search engines and some of popular search engines are Google, Yahoo, MSN, AltaVista and few more. Many search engines offer free submission and which can cause you spamming if you are indexed in it.
It is a total myth that if you don’t post content sporadically in your site then it will be deleted from search engines. It is very rare happen that your sites is deleted form the list of the search engines unless you commend something very absurd or abusive. All you need to update your site in regular interval and make changes but you don't need to submit them every month.
It is very Manual and automatic submission are always been an undecided topic. Many believe automated submissions are useless and sometimes your website is not indexed if submitted automatically. Though many major search engines don't prefer automatic submission due to spamming. But there are many search engines where you can easily submit your website automatically. It's a long and tiring job to submit website manually in every search engine. So, you can rely on automatic submission also.