I just got my empennage for christmas and I have previously built the tool box kit and the practice kit (small wing like structure). I think the practice kit is much more helpful. I actually ordered a second one to practice on before I got into the more expensive parts. The first one didn't turn out perfect
. The practice kit comes with a more complete set of instructions on the basics of metal prep. These are pretty cheap so I would suggest you order one if you are considering going further.
You might also want to consider taking one of the EAA sheet metal classes. That should at least get you started with the very basics of how all of this stuff goes together. Its not difficult but its different than probably anything else you've done before.
I'm still a beginner but all of these things did help me make the decision that I could indeed build a plane, and I liked doing the work.