How to check supplemental pages of my site

What is the exact method to check supplemental pages of my site.

 

You mean how much of your pages are listed in supplemental results?
I am afraid, there's no easy way available. But, theres a post in SEOMoz you may like.
http://www.seomoz.org/blog/checking-the-number-of-supplemental-results-for-a-specific-domain

 

Try this:
site:www.yourdomain.com/*
If your web page not there, it is suplemental page.

 

type this, site:yoursite.com