There are community forums setup online for virtually every niche, industry, or topic you can imagine. The internet is a prime place for like minded people to talk to each other. 9 times out of 10 you can find a forum for your industry just by typing in [your industry]forum.com or searching for “[Your Industry] Forum” on Google. Find the forums in your industry with the largest user base, start posting there and become an active community member. Most forums will allow you to leave a link to your website in your post signature, so the more you post the more traffic you get.
The leading search engines, such as Google, Bing and Yahoo!, use crawlers to find pages for their algorithmic search results. Pages that are linked from other search engine indexed pages do not need to be submitted because they are found automatically. The Yahoo! Directory and DMOZ, two major directories which closed in 2014 and 2017 respectively, both required manual submission and human editorial review. Google offers Google Search Console, for which an XML Sitemap feed can be created and submitted for free to ensure that all pages are found, especially pages that are not discoverable by automatically following links in addition to their URL submission console. Yahoo! formerly operated a paid submission service that guaranteed crawling for a cost per click; however, this practice was discontinued in 2009.