Help Please, My Burb is protesting...

[GMCjunkie]

I just dont think she appreciated having to get up and go to work today. I admit shes been runnin a little rough lately, and the weather has been getting colder. I know shes due for new plugs etc. But, This morning she started hard, and as I was driving, outta no where, she died, I pumped the gas and she came back to life, died again this time I put er in N and restarted , she started strong, no struggling. I was a little low on fuel, but not sucking fumes. I got her to the Chevron, put about 1/2 tank in her and she ran fine all the way to work, (14 mi). AFTER work, I let er idle and warm up, shes still runnin a little rough, but runnin. I start home, get about half way, she dies, (no warning, no sputtering or anything, just ....off) Then just as I throw her in N to restart, she starts up on her own and BACKFIRES, 3 times. Prolly scared everyone with in a country mile chitless, myself included.
Fuel filter?? Plugs?? Could the starting hard in the mornings be the carb?? or choke?? Im pretty sure I need a new choke spring, had a guy order one for me but it was the wrong one, (mine was under the one he ordered was over or vice versa) Where can I get a NEW correct spring?? What could the problem be?? Shes NEVER back fired before.
Thanks for the help.
junk