Just curious, but why would you want to do that? Neulevel offers an excellent paid search facility for .biz names. But that's the only registry I know that offers this kind of sophistication.
Seeing as I often put the domain name in as the registrant to simplify sales, and I use about 6 other names when I don't do this, I'm not sure it gets you anywhere.
I also supply an email address for clients so that they can avoid spam, so that won't help either.
This question was asked by one of my clients and thought this would be a good place to find out for him.
I agree with you guys, the end result would not be accurate. I also often register with a different registrant profile and different email address.