Now the Pro's already know this so this tip is for you the starter-uper
Using rough gestimation I can say that Google is the predominant search engine for about 80-90% of the world. The problem we have today is tunnel vision, we focus to much on trying to get on google we ignore what is literally thousands of hits.
What I did when I first started was focus on the lesser but still popular search engines.
Then using the traffic from these lesser known sites I then optimize for google which in turn helps me get on google a lot faster then I would've if I just concentrated on google in the first place.
Saves you a helluva lot of money to.