Before the flaming commences, I thought I would lend a hand...
Concerning the radiator, coolant leaking topic, there have been a lot of threads recently about this. It would be best to post in one of the existing threads, rather than start a new one. Not only is it better forum ettiquete, but you're far more likely to get an answer. I think there was a thread updated today about this issue. If skimming the last few dozen thread subjects doesn't pop up anything, try the search feature.
With part numbers, I found this website to be useful:
http://www.courtesyparts.com/pathfinder ... _6834.html
Most of the parts can be ordered right from there, for a far better price than going to your local dealer, also.