I have officially given up trying to use gschem. I can place components (and even create new symbols), but I have had no success connecting pins with wires. It is possible that I am an idiot, but I don't think I have to go too far out on a limb to claim that gschem isn't the most user-friendly of programs.
Fortunately, there appears to be a nice alternative called kicad. The problem of parts I need (e.g., ATtiny2313, ICM7212) not being in the default symbol library is still an issue, although some web searching did eventually turn up symbols for the parts I needed.
Update: I was able to connect VCC on the ATtiny2313 to +5V! I'm going to tentatively say that kicad rocks.