One very important way to get better ranking in google and yahoo search engines is to have as many links linked to your site. Not just quantity of  links but also the quality of the links are important also. Spiders crawl through the internet when search engines are used searching for content that has keywords that are simular to the keywords used in the search engine. The most heavily quailified site to have linked to your site are the ones that end in .gov, .edu, .K12 or .org ..  Here is a great free tool for you to use to search websites to find out which links are linked to a website. It is a great way to spy on the competition that is ranked high under your keywords and try to link to them, also for better ranking.

Here is the link