SVX shakes badly

[dwd1985]

Whenever I start my SVX, and am stopped in park or driving at low speeds, it runs very roughly. It feels fine when I drive at mid to high speeds, but in the low speeds or stopped, the whole car is shaking very roughly. It was fine all of yesterday until the afternoon. It had only been sitting for about 2 hours, and then I drove it home, and it started running roughly. Then I figured it would clear itself up, but it did the same thing today. No engine codes or anything. So Im sure that what everyone will tell me is that I probably have a misfiring cylinder, and need to unplug the injectors one by one to find out which one it is. However, where are the injectors? Every obstacle I come to on my SVX, I need to know the part location before I try it, so can someone give me a vague description of what they look like? Or a picture would be better. I am sure that many of you are reading this and laughing saying "He doesnt know what the injectors look like? Ha Ha!" But I dont, so forgive me.
Will replacing the spark plugs help this out?