new to jetta seen looking for advice

i posted this on behalf of my causin who just got a 92 jetta gl (i know its not the best one ) but oh well .. what i was wondering is if anyone knew and web site were i could find parts for his car or no of any brands that make intakes for it or no any horsepower tricks for it since it lacks hp alot (100hp i think) so thats kinda low so im open to suggestions...i dont know what the engine code is or anyhting but i was hoping someone could help me on that one too i think its a 1.8l 8 valve but im not sure .. it is a sohc though