high performance exhaust system

Though i realize that not many people try to invest in a 1993 VW Passat GLX VR6 in such a way, but i am looking to put a high performance exhaust system into my car, the only problem is that i haven't had much luck in finding any high performance exhaust system for that car, i realize that sometimes certain systems for other cars might fit mine as well, i simply don't know what i should do, any sites, suggesstions, etc will be helpful