Here's the deal. I lay down some tracks in Sonar. When the tune is done, I chop off, say 10 or so measures in the editing process. I export the thing. Low and behold, there's a long chunk of silence at the end that equals 10 or so measures. So I have to go back into Sonar and manually delete the ending envelope nodes (volume and pan) on every track. Now, Sonar will export the song with no "tail" to chop off.
 
Is there an easier way to do this? I tried opening up all the track envelopes, highlighting them, and then deleting, but this only moves the end nodes. I'd like to get rid of them.

You can hit cntl-a to select all tracks and then range select (click and drag) in the ruler just the time you want to export.
 

Use the time ruler to drag select the section you want to export. Anything out of that range will be ignored. 
 
HTH.