Does the car smoke after idling for a while? I worked for 3 years with GM and was a diagnostic specialist with Autozone for 4-5 years... Mainly just educating employees and such. If you're close by either an Autozone or Advance, I'd say stop in and have them run an OBD2 diagnostic scan on it. It's free for cars newer than '96 and it will give you a good starting point. I'll try to help as much as I can though, on here...
Chances are it's not the coil, Generally speaking, A coil will start to show signs when it's hot (loseing fire) and oil on the plugs would indicate either the rings or valve seals. If it smokes a little all the time, it's rings, If it only smokes after prolonged idling it probably valve seals... Get it scanned first. With all the sensors controlling timing now a days it's a good idea, before you start tearing into anything. Heck it could very well be something as simple as a vacum leak causing it to run rough, but the oil on the plugs is a sure sign of future, more serious problems..
[b][color=#FF0000]If your brain is part of the process, you're missing it. You should play like a drowning man, struggling to reach shore. If you can trap that feeling, then you have something.
[/color][/b] [b]Peace of mind. That's my piece of mind...[/b]