I don't think you need a new stator or electromagnets to use the GM alternator. It will need to get up to the speed it would on an engine though. If you use 12v batteries and inverters you can expect about 800 watts of a/c power from a 90 amp alternator. You will have to look into the gearing, but probably only a fan belt with a 8" pulley on the blades would work with the standard diameter pulley the alternator comes with. That would basically work for the blades operating at 1000 rpm or so. If you need it to run slower, say 500 rpm, then up the pulley size to 16" diameter on the blades. You will need to do some more research on what size blades you need for what would be approximately a 1.5 HP load based on your nominal wind speed.
You can also run more than one alternator if your blades are big enough to deliver more power.
I'd look at some RV dealers for the inverters. They have them in all sizes.
Feeding the power into your breaker box requires equipment that is probably not worth the cost, imo. I would find something to run off of the windmill that you could isolate, myself.