If that is like that magic game you can pick up packs of those cards in the 7-ll stores. And yes it is hard to play as there wouldn't be any english instructions for you to learn how to play. Everything would be in Chinese. If you can read and understand chinese you will be able to find those cards at 7-ll though, but it's a long game from what I've heard. 

Hi Peter, I am not Chinese and didn't study Chinese until college, but I have learned to play 三国杀。At work, my whole team is Chinese, so we play every Friday at lunch. On my first week, I didn't know how to play, but I read the cards and listened to my coworkers explain how to play in Chinese, and I actually won as 内奸 (renegade). 

If you have trouble reading Chinese, the game will be challenging for you to learn, especially the characters each with their specific abilities (similar complexity to Magic the Gathering cards). The core mechanics are quite simple, however, and can be learned by playing Bang, the game 三国杀 that was ripped off of. 

Ok, I have to go now - we are about to play!

try this website 

http://sanguoshaenglish.blogspot.com

 also the Wikipedia article may also be helpful:

http://en.wikipedia.org/wiki/San_Guo_Sha

I am also learning this game with my friends.... good luck