As far as I know, a 95 Regal doesn't have a distributor. The spark timing is determined by the computer.
If you look at the plugs, you will see wires that go to three "black boxes" bolted to the side of the engine. These are the coils. You can buy a coil tester from KMS tools or similar stores that sell automotive tools. It comes with instructions. Sometimes a coil can be intermittent, though. If you know some one with a 3.8, you could try swapping coils and see if that fixes your problem.
Wires are cheap, so I'd replace them anyway. I usually stay with GM wires, they seem pretty good. Just make sure they follow the same routing as the old ones you remove. I usually do one at a time so I guarrantee the go on the way the came off.
There are other causes for your symptoms, but I consider plugs AND wires to be part of a regular maintainance thing. If you get your hands on a good scantool, you can determine what plug is misfiring. Then you can move coils around and see if the missfire moves to a new cylinder. If so, then it's your coil.