I noticed googlebot visited my site the day after I put it online. I didn't submit it to google and there was no one linking back to my site...so how'd google find it? Was it because my registrar linked to it or what?
Google spies. Did you happen to put AdSense on it? Also, often times there are services out there that report on recently purchased domains. These reports will sometimes link to the domain in question. Do a search for your domain name in Google, without the www and with the domain name in quotes, see if anything comes up. -Michael
i have the same experience before. i had a new domain which i never submitted to any search engines or build links for it but it was still indexed by google.
LOL... But you do have something there, it seems that if you run certain Google services you may be picked up: http://www.mattcutts.com/blog/crawl-caching-proxy/
Another way to check would be to see if Yahoo Site Explorer lists any backlinks. If its enabled you could check your backlinks in the Webmaster Console as well.
Yeah you never know what kind of weird backlinks are created just from you having the site. Maybe you posted something in your hosts forums and your name has a link to it. All kinds of weird stuff.
No they don't... Why would they, anyway? Google isn't "the internet". It is just a site. There is no need and no advantage for registrars to submit domains to Google. Waste of their time and resources and unless they say they do that in their T+C's, many customers wouldn't be very happy.
That wouldn't matter either. The short and simple answer is that just because you didn't point any links at your site doesn't mean that there aren't any links pointing at your site. -Michael
Outbound links can also get your site in the index if you link out to a site with referer logs or stats that are getting picked up.