Inserting voice over dub

I’m using Windows 2007 and have recorded voice over dubs on a WAV file. The voice over dubs are showing each as a separate track. How do I combine the tracks together into one WAV file? Do I just EXPORT the whole thing and it does it automatically? Or is there something I have to do?

Good guess. Yes it does.
Check that the whole thing plays correctly and does not “clip” (distort) before you export. When multiple tracks play together the overall level increases so it may be necessary to reduce the track levels. There is a “gain” slider on the left end of each track for adjusting the “mix level” of each track.

There’s some tutorials here that may be of interest: http://manual.audacityteam.org/manual/help/manual/man/tutorial_recording_multi_track_overdubs.html