If you are a blog or website publisher, you might want to find out what is your link popularity, and who is linking to your site? One of the best ways to get noticed by search engines is incoming links. The greater the number of in-bound links, the higher the link popularity.
Here is how to find the number of incoming links and backlinks.
Note: Replace your URL in the place of domainname.com
Google
Go to Google and type : link:domainname.com
If you have Google Analytics account you can see all of the incoming links.
Yahoo
Go to Yahoo ( Site Explorer) and type : http://domainname.com
Altavista
Go to Altavista and type : linkdomain:www.domainname.com
Alexa
Go to Alexa and type : http://www.alexa.com/site/linksin/domainname.com