Ah, Warlord has posted some rules to add Samurai aspects to your Pike & Shotte armies. Makes me want to get some borscht and watch Battleship Potemkin (because now I'm just messing with you). But the fact that Warlord has posted up a new set of rules to field Japanese forces isn't messing with you. That's true.
The rules are free to get. Just head to the website and you can find the .pdf. From there, it's a simple matter of figuring out what samurai you want to be a part of your feudal Japanese forces, then take them out against various European forces, looking to see who had the best soldiers of the era.