1998 Chevy Monte Carlo Engine misfires and dies on startup

Ok first let me say I'm not mechanically enclined at all so any parts I may mention will not be the correct term but ill do my best so bare w/ me please. I have a 98 Monte Carlo that has not been well maintained w/ 117k miles on it. A few days ago when driving to work once I got to the parking garage it just sputtered and died. I restarted it and as soon as I put it in drive it died. I had to get to work, third shift, so I left it until I got off work and same deal startup, sputter, die so I got a ride home and went back that after noon to look at it w/ someone w/ a little knowledge in cars. It was worse. It took 3-4 tries just to get it started and it would sputter knock and shake the car violently and die. My friend told me it was misfiring. If I started it and pushed on the gas a little it would run sputtering and knocking for a little longer, 30-40 sec then die. Now I was told by my friend and many others this could be a multitude of issues but due to not having alot of money and not able to find a good shop around, at leastnot yet im still looking, to give me a free estimate im tryin to narrow it down. We know its not the coils as we tested them and two where not so good and we did replace them but only change it made was it was easier to start but still sputtered misfired shook violently and died. We know its not the regulator. Not sure the full name there but that little mini computer that tells it when to fire. Becuase we had that tested too. Now as I said this car has 117k miles and poorly maintained has never had a tune up so he suggested the spark plugs. The thing is thanks to chevy engineers enjoying making my life hell lol The only way to get to the back three is to roll the engine and obviously I dont have the skill for that and a shop wants upwards 400 bux to do it. By all means if/when I get this car running I definitly need this done reguardless how ever at this time I need it to run to get me to work and my kids to school and I cant afford to pay 400 and not have it running yet so my question is would bad spark plugs cause this bad of an issue or should I be looking elsewhere?

Thanks for any info