Just wanted to recommend this tutorial for pathfinding:

http://www.policyalmanac.org/games/aStarTutorial.htm

I managed to implement pathfinding into my game using this article, and it is very fast and efficient! I was really shocked when it first worked haha.

Here's the videos of the pathfinding in action:
http://www.youtube.com/watch?v=ugcEO...feature=relmfu
http://www.youtube.com/watch?v=ZRLzs...feature=relmfu