How to know the Legitimate Internet Marketing Services that Do Not Violate the Search Engines' Policy

There are lots of internet marketing services and based on what I have learned from reading the policy/rules and regulation of one of the top search engines in the world, I should beware for those internet marketing service that instead of getting my website into the top it may violate the search engine's policy. Violating this policy means my website may not be seen in their search list anymore instead.