Google shows only 10 results in its first page, but it does not mean that other sites which do not come in first 10 pages are not reliable. The websites who are not in top results may have made enough efforts to appear in top results. These efforts include social bookmarking, article submission, blogging, directory submission etc.
There is a cut-throat competition running between all website owners to get on the top results. Google ranks all websites based on some factors and it is necessary for a website owner to know all these factors to achieve high rank in Search Engine Result Pages (SERPs).
There are some SEO basics which must be known to the people who are involved in online marketing campaigns. The main factor in achieving success in SEO is choosing keywords. This is the main step in SEO. Keywords should be specific not general and common. Less common and unique keywords have less competition, thus less efforts can make them appear in top results. There are many keyword research tools available for suggesting you the appropriate keywords for your site. Google keyword research tool is one among them. Using such tools will help you in choosing keywords relevant to your site. There are also tools available that help you to know the current competition for keywords. If title and URL (Uniform Resource Locator) are used well, then it will be beneficial in SEO of the site.
Content is also very important factor in rank of a site. Incorporating Keywords in content can place a site in top results. But do not overuse keywords in content.