Thanks guys!! My mechanic has been my mechanic for YEARS, and this is the first time I've ever had issues like this. Half of the stuff on this list was stuff I'd either found suggested on here, or suggested by my hubby. In the beginning, we weren't getting the misfiring (or ANY) codes, she was just stalling out. My hubby has access to a diagnostic computer (not the cheapest one out there, but not the most expensive one either), he brought it home from work, saw the misfire on 2 cylinders (can't remember which ones at the moment), and wanted to change the plugs. His dad retired from autolite, so since he was paying (and it was after 5), the autolites went in. The second plug change was totally my doing, as I have heard not so great things about autolites both on the web and from a few "backyard" mechanics, so I went ahead and had the Delcos put in. The only things that my mechanic actually diagnosed were the coil pack and the injectors, both of which I was able a good deal on the prices. My hubby is a local body guy, so he gets the shop discount on dealer parts (thank god).
I just registered for the ecotec forum and I'm going to try there and see what they suggest, so if any of you are over there too, don't be surprised to see me!! :-)
And, for the record, I'll never give up on YC....I've found way too many good ideas (like painting my cup holders, among others) that I want to do to mod my car a bit. Well, once I get this issue taken care of, at least. :-)