John Jantsch...
http://www.ducttapemarketing.com/john-jantsch.htm
http://www.ducttapemarketing.com/

And
David Frey...
http://www.marketingbestpractices.com/

Amongst Many other's Don't seem to have any problems Finding their Niche customers.

But of course we can all have different opinions on what Works and what doesn't.

Phil