Google wasn’t there a couple of years ago.
No one is stopping you from building a rival to Google.
OK, how much will you contribute to an alternative?
Serious question, not flippant.
A number of people are trying... there are a lot of other search engines out there, most of them highly specialized.
The Search Engine List
Cuil (Pron: "cool") is the newest trying to take on Google. Supposedly searches more pages and indexes more documents than Google. Ex-Google people have done this startup.