Customising Jetta

I'm looking to dedo my 89 Jetta. I'm not sure where to start. It runs great now, but I'd like to make it a little faster. Is there any engine mods I can get for the 1.8 8V? and where do I get them? Or do I need to go to the 16V? Also where do I find Euro Grills with the round headlights? Everything I'm going to customise myslft I think. I appreciate the imput. Thans DaButcha.