find an email id - startup idea?

One problem that I face everyday is finding email ids of people whom I dont know. If you do business development / marketting / sales, then you know what I mean. There exists no easy way that I know. 

Is there any? Dont tell me linkedin.

It would be cool if there is a service which can scrapes all the websites and creates a database of people and email id, and provides an easy search mechanism.

Startup anyone? :)

~Sri