Why Aren't There More Transitional Fossils?
Transitional fossils bridge gaps between two species. Due to the difficulties in creating fossils in the first place, and the fact that speciation sometimes occurs very quickly in small groups, transitional fossils can be rare in the fossil record. However, even given these circumstances, there are still thousands of transitional fossils known to science, including those illustrating the evolution of modern fish, the transition of fish to amphibians, amphibians to reptiles, reptiles to birds, reptiles to mammals, and the evolution of human beings (as well as many other species).
Please see this video for great examples of transitional fossils: http://www.evolutionfaq.com/vi
Also, see this Wikipedia page detailing just a partial list of transitional fossil examples: http://en.wikipedia.org/wiki/L