you can add your website to google webmaster tool........................add a robots.txt to allow or disallow the robots and sitemap to crawl all of your website's pages
Definitely worth it. Try and find a service that adds you to a lot of search engines in one process. I have lost my link and I apologise for that.
yea,it is worth it. This is to let google know about your site and get indexed in their search engine
Yes, definitely it's a needed one. This is the first step i will do to make the website indexed in google.