Simply too broad a subject to answer quickly. Lots of information is available on Google itself
http://www.google.com/corporate/tech.html[
^]
Links are important, but *quality links* are more important. Links that provide relevance to the subject
Simply spamming the internet with links to your site could fall under 'Link Farming'
Have a read up on Black Hat SEO etc
http://en.wikipedia.org/wiki/White_or_black_hat[
^]
http://en.wikipedia.org/wiki/Link_farming[
^]
Google will find your links as it's bots crawl the web and index pages.