njlonghorn, good for you on learning to do repairs yourself. learning to true and tension a standard bicycle wheel will be the next step, but it *is* more difficult and involved than the things you've listed. A real truing stand will be the best way to do it (and to learn), and you'll probably want to start with an old wheel - try loosening all the spokes, and then building it back up. I'd recommend Sheldon Brown's instructional on wheelbuilding (though there are other good guides) and start at "initial spoke adjustment."
http://sheldonbrown.com/wheelbuild.html

Good to know you weren't throwing money down a wal-mart bike. But if the wheel needed a lot of work truing and tensioning, $33 for the spoke+labor isn't unreasonable. Assuming the wheel is now properly tensioned, it should be a lot more durable.

If the wheel was poorly-tensioned before the spoke broke (a likely cause), it's possible that more spokes on the non-drive-side of the rear wheel are fatigued and may break. If one spoke on a wheel breaks, I usually consider it a fluke. But if more start breaking, there's a general fatigue problem.
If the bike shop trued and tensioned the wheel, hopefully they've shot down long-term danger to the wheel. Cross your fingers.