Many years ago, we received a copy of Illustrator 0.9b. Basically all it HAD was the pen tool. LOL
I think the best way to get comfortable with the pen tool, aside from JJMack's link to that nice tutorial, is to spend lots of time just playing around with it.
Bezier, a French engineer from the 1900's, invented/discovered an elegant way to define a curve using two anchor points and two control points. That's what Illustrator does with its pen tool. It's called the Bezier curve, and once you figure out its elegant interface, you will find you can draw virtually any shape with it.
BTW, you might consider also posting your query in the Illustrator forum. :+)
