I agree with Vlad, you can learn a lot from local builders and volunteers for free. I have no idea how much the courses cost, but I'm a really cheap person.

I'm alomost certain you could find someone within a reasonable distance to help you get started. They'd probably let you come over and help drive/buck rivets. drill, dimple, deburr, etc for free.

Heck, when you get started, they may even come to your place and help you. Not mention, they'll probably be ahead of you enough that when you get to the fiberglass part, they'll have been there done that and give assistance there also.
I'm not knocking these classes. But unless you're out in the middle of BFE, with absolutely no one within many many miles. I'd say save your money.
This is strictly my opinion only.
Marshall Alexander