In our area, we have a career/employment search type place that provides this kind of information to people. It's like a guidance counselor provider for people out of school. I don't know if your son is still in school or has left, but there are much better places to get this kind of info than a mom site - just sayin'.
If I was trying to help my son decide on a career - that's where I'd send him. He should be leading this search at this time, really. There's also online info out there. I would suggest if he doesn't know what he's suited for, to do one of those match up skills/interests to career option type tests. They often have them at college sites or just google it.
Again, these career/employment type organizations (I'm sure they would have one in your area) have these kinds of things. A counselor could go over it in person with your son.
I really would recommend it. My kids did it at school. We had people come in and as parents we did it with ours, but I've seen them online too. Start there. Far easier than coming up with possible careers and then asking people. Narrow it down to suit his personality type.
Good luck.