I wleded up 2 old jeeps using a Craftsman MIG w/flux wire, no gas. I did countless other projects including a huge deck railing and some p-car stuff with that welder until it finally died last weekend, about 10 years after I bought it.
Anyway I decided to "upgrade" to this welder....
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=6271
It's 220V, and seems to do a better job than the old 110V Craftsman. Pretty good duty cycle.
IMO, for the hobbyist, a cheap MIG using flux wire is enough to do 99% of your home projects. Yea, it spatters a bit and I'm not going to win any contests with my welds, but it works really well for the money. Maybe I’ll check out the fancy gas setup one of these days.