I served an apprenticeship (union). One of the posts above pointed out that there are some non-union state approved programs & I've run into some of the guys that have been through them &you really can't tell us apart.
A lot of it comes down to desire though. I know too many guys (union & non) that quit reading & studying as soon as they have their license. This is OK if all you're going to do is bend pipe & jerk wire. But it really kills me to hear "When did they change that?"
I read 4 1/2 trade magazines a month and I usually buy a book or two a year. And spend time on the electrical bulletin boards.
So, keep reading, keep asking questions & see if you can't get into an apprenticeship or trade school. This stuff can be really tough to pick up on your own.
Good luck.
Tom