Sounds like you're at least semi-self employed. That's one good way to learn since you're obviously inspired to do so. (And no doubt a little pissed off. "Hey, I'm not relying on an employer. I did this on my own and I've got to pay WHAT in taxes?")
+1 on researching all the forms. You'll then add to your knowledge each year. Keep up to date on taxes that come and go and depend on eligibility and where you live (deducting sales taxes, child tax credit, etc.) I always look for those January stories on "Ten Tax Changes You Should Know." Most of them are pretty basic, but inevitably there's one new wrinkle that saves me $500 somewhere.
I'm self-employed, own a small business, rental property, etc. So there are a lot of moving parts. But I'm glad I understand them because nobody is going to look out for your money at tax time better than you will. I'm always amazed at friends who work for an employer and have nothing more than a mortgage and a 401K and actually hire someone to do their taxes that probably should take 10 minutes.