MichaelBluejay - 2:30 pm on May 25, 2010 (gmt 0)
If any other site links to your site, Google (and all the other search engines) will find out about it.
If no one links to your site, it doesn't matter, because a site with no links to it isn't going to rank very high in the search engine results pages (SERPS).
Now, before you ask "So how do I get my site to rank high", that's what half the millions of posts on this forum are about. Start doing some reading. Good luck. :)