Is something wrong with your stock coils? I recently saw several people run mid 13s at the track with the stock series ii coils. Basically what I'm saying is that I think you can do better mods for the money. You mentioned a 3.4 pulley. From my experiences you need a well designed intake and one heat range colder spark plugs. I run autolite copper plugs but have also run the ngk tr55s. The parts store will often try to sell you a platinum or irridium plug, Iridium will work but copper is 1/5th the price. Most seem to prefer copper on a modded 3800sc. MSD wires are decent quality but you can get just as good for cheaper.
Have you scanned your car with a scantool for Knock or (KR)? This is very important when you drop a pulley size to make sure your car is running properly?
There is a large afermarket for your engine. Many vendors out there sell parts for these cars and packages to get you started.
I've personally bought stuff from Intense Racing and ZZ Performance and both were good to me. There are several other sites out there...
I'd reccomend you read this article about modding a bonneville: