Google is not really the only one, there are lots of other around the place that are worth looking for.
But like Timme said it would need you to have traffic first.
If you have low traffic its best to go for a PPC like google as one click can cover thousdans of views
If you have millions of views a day, then you have to see your click throughs. If its high then stay with PPC if its low try a PPM engine.